refactor: replace helm-update-image with yaml-update

[krancour]

Fixes #2939

This PR:

• Reverts most of what #2925 did to the helm-update-image step. There is no sense improving that step and deprecating individual fields if the entire step is going to be deprecated and replaced. This would only have led to confusion.

• Deprecates helm-update-image.

• Adds a new, generic yaml-update step that is essentially an improved/stripped down version of the helm-update-image step.

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[codecov[bot]]

Codecov Report

Attention: Patch coverage is 84.76190% with 16 lines in your changes missing coverage. Please review.

Project coverage is 50.92%. Comparing base (b75c455) to head (1c0e939). Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/directives/yaml_updater.go	77.41%	13 Missing and 1 partial :warning:
internal/directives/helm_image_updater.go	95.34%	1 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2941 +/- ## ========================================== + Coverage 50.86% 50.92% +0.06% ========================================== Files 278 279 +1 Lines 25113 25180 +67 ========================================== + Hits 12773 12823 +50 - Misses 11651 11666 +15 - Partials 689 691 +2 ```

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[krancour]

Something is wrong here. The commit that undoes the helm-update-image changes is missing.

Looking into it.

[krancour]

Fixed now.

a20442c371ac74d652fa96ac3eebaea1e6b73be7 rolls back most recent changes to helm-update-image, but keeps non-breaking schema improvements and the additional tests that had been added.

[Marvin9]

@krancour we also need to update UI as discovery mechanism of runners/registries is not automatic.

Should I replace helm-update-image with yaml-update?

[krancour]

@Marvin9 possible to have both for now and then remove helm-update-image in 1.2?