Improve test failure logging for TestBallastMemory

[jpkrohling]

This change improves the failure message for the TestBallastMemory. While this won't solve the problem, it will help understand if we are barely above the limit, or if the test went considerably above the max.

Signed-off-by: Juraci Paixão Kröhling [email protected]

[jpkrohling]

@owais, could you please review this one? You seem to have worked on this part in the past. I'm not sure I understand all that is happening in this test. For instance: is there a relation between the ballast size and the RSS? Is the max RSS here an absolute value, or should we fail only when the RSS is, say, 10% above Max RSS?

[jpkrohling]

Luckily, the test failed, which allows us to test the PR :-)

2021/05/20 12:34:56 Agent running, pid=7398
    assertion_compare.go:342: 
        	Error Trace:	e2e_test.go:87
        	Error:      	"71" is not less than or equal to "70"
        	Test:       	TestBallastMemory
        	Messages:   	[]