feat: display flavor assignment attempts in events

[mykysha]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Add information about why some flavors were not chosen in favor of the other to the events at the admission.

Which issue(s) this PR fixes:

Fixes #7137

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

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[mykysha]

This PR records flavor attempts tried, however as flavors get chosen on the first-to-fit basis, it may introduce some misleading results.

One example would be that not all flavors are tried, resulting in an incomplete list of the flavors that could be chosen.
Another, and more serious one, would be that sometimes we might not reach the failure point for one of the flavors attempted, resulting in a message that is falsely marked as "Fit". As an example, in the test "multiple flavors, leader worker set, workers request GPU, leader does not request GPU, fits" in the flavorassigner_test.go there is one flavor that should be Fit, and another that should be NoFit because of the missing GPU resource. In fact, if another two resources get checked first, and then the fitting flavor is chosen on the gpu check, we do not get the missing resource message, hence do not fail the check.

One potential option would be to disregard attempts that have not been tried for all the requested resources, potentially severely limiting the information returned, but making it more true in the end.

[mimowo]

@mykysha please set release note

cc @mbobrovskyi @mszadkow @IrvingMg please review