🌱Remove semantic merge from bootstrap controller

[sedefsavas]

What this PR does / why we need it:

This PR removes semantic merge code that was used to add hash annotation during KCP machine adoption. This is no longer in use.

[vincepri]

/milestone v0.3.7
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: vincepri

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[vincepri]

/assign @fabriziopandini

[k8s-ci-robot]

@sedefsavas: The following test failed, say /retest to rerun all failed tests:

Test name	Commit	Details	Rerun command
pull-cluster-api-apidiff	652bc7a	link	/test pull-cluster-api-apidiff

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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[sedefsavas]

/test pull-cluster-api-e2e

[vincepri]

/lgtm