Apply currently parses the yaml object 3 times, please remove 2

[apelisse]

This is super expensive and not needed at all since we don't have to
reparse the entire object. Remove all allocations but the first one.

Using the benchmarks from #82847

benchmark                                 old ns/op     new ns/op     delta
BenchmarkApplyNewObject/Pod-12            2348652       1505817       -35.89%
BenchmarkApplyNewObject/Node-12           4569184       2656921       -41.85%
BenchmarkApplyNewObject/Endpoints-12      90670338      38864724      -57.14%
BenchmarkUpdateNewObject/Pod-12           1073668       1067810       -0.55%
BenchmarkUpdateNewObject/Node-12          1510927       1531581       +1.37%
BenchmarkUpdateNewObject/Endpoints-12     5866342       5929641       +1.08%
BenchmarkRepeatedUpdate-12                937133        967885        +3.28%

benchmark                                 old allocs     new allocs     delta
BenchmarkApplyNewObject/Pod-12            8819           5028           -42.99%
BenchmarkApplyNewObject/Node-12           17696          9528           -46.16%
BenchmarkApplyNewObject/Endpoints-12      409593         176869         -56.82%
BenchmarkUpdateNewObject/Pod-12           3977           3977           +0.00%
BenchmarkUpdateNewObject/Node-12          5742           5742           +0.00%
BenchmarkUpdateNewObject/Endpoints-12     21442          21442          +0.00%
BenchmarkRepeatedUpdate-12                3027           3027           +0.00%

What type of PR is this?
/kind cleanup

What this PR does / why we need it:

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[k8s-ci-robot]

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[jennybuckley]

/assign

[jennybuckley]

/retest

[jennybuckley]

/lgtm
This is a really big improvement!
Also, I think we can be confident that this doesn't reintroduce the problem fixed by #75277 since the tests are all passing