Bug fixes for status patching and late initialization patching

[vijtrip2]

Description of changes:
Commit#1

• Adds the implementation of AWSResource.DeepCopy() method. Reset the object status after patching resource metadata & spec. runtime#48

Commit#2

• Fixes the patching bug in lateInitialize code to unblock sagemaker team
• BUG: rm.LateInitialize() method was adding lateInitialized fields to the same object passed in the parameter and returning as output.

        lateInitializedLatest, err := rm.LateInitialize(ctx, latest)
	rlog.Exit("rm.LateInitialize", err)
	// Always patch after late initialize because some fields may have been initialized while
	// others require a retry after some delay.
	// This patching does not hurt because if there is no diff then 'patchResourceMetadataAndSpec'
	// acts as a no-op.
	if ackcompare.IsNotNil(lateInitializedLatest) {
		patchErr := r.patchResourceMetadataAndSpec(ctx, latest, lateInitializedLatest)
		// Throw the patching error if reconciler is unable to patch the resource with late initializations
		if patchErr != nil {
			err = patchErr
		}
	}

• Since lateInitializedLatest and latest were same object, above patchResourceMetadataAndSpec call sees no diff and does not patch lateInitialized fields into etcd.
• This PR solves the bug by adding lateInitialized fields in a copy of latest and returning that copy (without modifying latest)

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[ryansteakley]

Tested these changes locally using late initialize for trainingjob field and it now sucessfully late initializes the field and the resource is correctly patched

[a-hilaly]

Neat 👍

[RedbackThomson]

/lgtm

[ack-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: A-Hilaly, RedbackThomson, ryansteakley, vijtrip2

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