Check for duplicate keys in check-json5 builtin hook

[j178]

For #1368 (comment)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.33%. Comparing base (0e934c3) to head (b7cea7b).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1387      +/-   ##
==========================================
+ Coverage   90.30%   90.33%   +0.03%     
==========================================
  Files          82       82              
  Lines       16147    16147              
==========================================
+ Hits        14581    14587       +6     
+ Misses       1566     1560       -6     

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[github-actions]

📦 Cargo Bloat Comparison

Binary size change: +0.00% (22.4 MiB → 22.4 MiB)

Expand for cargo-bloat output

Head Branch Results

 File  .text    Size        Crate Name
 0.3%   0.8% 71.5KiB        prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.2%   0.6% 54.6KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 49.8KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 46.1KiB         prek prek::run::{{closure}}
 0.2%   0.5% 42.9KiB         prek prek::cli::run::run::run::{{closure}}
 0.2%   0.5% 42.7KiB         prek prek::identify::by_extension::{{closure}}
 0.2%   0.4% 35.1KiB         prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.1%   0.3% 31.6KiB        prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.1%   0.3% 29.2KiB  serde_json? <&mut serde_json::de::Deserializer<R> as serde_core::de::Deserializer>::deserialize_struct
 0.1%   0.2% 21.6KiB         prek prek::archive::unzip::{{closure}}
 0.1%   0.2% 21.3KiB clap_builder clap_builder::parser::parser::Parser::get_matches_with
 0.1%   0.2% 21.0KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 20.8KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 19.6KiB         prek <prek::languages::ruby::ruby::Ruby as prek::languages::LanguageImpl>::install::{{closure}}
 0.1%   0.2% 19.2KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.9KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.6KiB         ring ring_core_0_17_14__x25519_ge_frombytes_vartime
 0.1%   0.2% 18.2KiB   hyper_util hyper_util::client::legacy::client::Client<C,B>::send_request::{{closure}}
 0.1%   0.2% 18.1KiB    [Unknown] fe_loose_invert
 0.1%   0.2% 17.7KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
36.6%  91.6%  8.2MiB              And 19738 smaller methods. Use -n N to show more.
40.0% 100.0%  9.0MiB              .text section size, the file size is 22.4MiB

Base Branch Results

 File  .text    Size        Crate Name
 0.3%   0.8% 71.4KiB        prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.2%   0.6% 53.8KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 49.8KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 46.1KiB         prek prek::run::{{closure}}
 0.2%   0.5% 42.9KiB         prek prek::cli::run::run::run::{{closure}}
 0.2%   0.5% 42.7KiB         prek prek::identify::by_extension::{{closure}}
 0.2%   0.4% 35.1KiB         prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.1%   0.3% 31.7KiB        prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.1%   0.3% 29.2KiB  serde_json? <&mut serde_json::de::Deserializer<R> as serde_core::de::Deserializer>::deserialize_struct
 0.1%   0.2% 21.5KiB         prek prek::archive::unzip::{{closure}}
 0.1%   0.2% 21.3KiB clap_builder clap_builder::parser::parser::Parser::get_matches_with
 0.1%   0.2% 20.8KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 20.6KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 19.6KiB         prek <prek::languages::ruby::ruby::Ruby as prek::languages::LanguageImpl>::install::{{closure}}
 0.1%   0.2% 19.2KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.9KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.6KiB         ring ring_core_0_17_14__x25519_ge_frombytes_vartime
 0.1%   0.2% 18.2KiB   hyper_util hyper_util::client::legacy::client::Client<C,B>::send_request::{{closure}}
 0.1%   0.2% 18.1KiB    [Unknown] fe_loose_invert
 0.1%   0.2% 17.7KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
36.6%  91.7%  8.2MiB              And 19744 smaller methods. Use -n N to show more.
40.0% 100.0%  9.0MiB              .text section size, the file size is 22.4MiB