[#1315] Fix for workload prematurely being declared unhealthy

[tbr11]

Changes proposed by this PR

closes #1315

For immutable templates, their resource health is conditioned on the most recently stamped object. Prevents workloads stamping immutable templates to immediately be in Ready==False before later flipping to Ready==True.

When ResourcesSubmitted condition is MissingValueAtPath, the message is conditioned on the object's health condition:

• healthy: cannot read value [some-path] from healthy object [some-resource/some-name] in namespace [some-namespace], contact Platform Eng
• unhealthy: cannot read value [some-path] from unhealthy object [some-resource/some-name] in namespace [some-namespace], examine object, particularly whether it is receiving proper inputs
  unknown: waiting to read value [some-path] from object [some-resource/some-name] in namespace [some-namespace]

Release Note

bug fix for statuses on workloads being prematurely marked unhealthy

Cherry-pick branches

PR Checklist

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