Move external paramenters and resolved dependencies logic out of v2alpha3

[renzodavid9]

Related with: #1065

This is a refactor in preparation for v2alpha4 which uses in its majority the same logic as v2alpha3.

Logic and tests moved to chains/formats/slsa/internal to be able to use it from different versions:

• chains/formats/slsa/v2alpha3/internal/external_parameters/external_parameters.go => chains/formats/slsa/internal/external_parameters/external_parameters.go
• chains/formats/slsa/v2alpha3/internal/resolved_dependencies/resolved_dependencies.go => chains/formats/slsa/internal/resolved_dependencies/resolved_dependencies.go

Current behavior shouldn't change with these changes.

This refactor will be use as base to enable v2alpha4 for TaskRuns, diff can be preview here

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• [ ] Has Docs included if any changes are user facing
• [x] Has Tests included if any functionality added or changed
• [x] Follows the commit message standard
• [x] Meets the Tekton contributor standards (including functionality, content, code)
• [ ] Release notes block below has been updated with any user facing changes (API changes, bug fixes, changes requiring upgrade notices or deprecation warnings)
• [ ] Release notes contains the string "action required" if the change requires additional action from users switching to the new release

[tekton-robot]

Hi @renzodavid9. Thanks for your PR.

I'm waiting for a tektoncd member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[chitrangpatel]

/ok-to-test

[tekton-robot]

The following is the coverage report on the affected files. Say /test pull-tekton-chains-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/chains/formats/slsa/internal/external_parameters/external_parameters.go	100.0%	87.5%	-12.5
pkg/chains/formats/slsa/internal/resolved_dependencies/resolved_dependencies.go	60.0%	87.5%	27.5

[tekton-robot]

The following is the coverage report on the affected files. Say /test pull-tekton-chains-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/chains/formats/slsa/internal/resolved_dependencies/resolved_dependencies.go	60.0%	87.5%	27.5

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chitrangpatel, lcarva

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/tektoncd/chains/blob/main/OWNERS)~~ [chitrangpatel,lcarva] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[tekton-robot]

The following is the coverage report on the affected files. Say /test pull-tekton-chains-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/chains/formats/slsa/internal/resolved_dependencies/resolved_dependencies.go	60.0%	87.6%	27.6

[chitrangpatel]

Thanks @renzodavid9! If there are still nits that need to be resolved, we can do that in the next PR. Let's unblock your work. /lgtm

[chitrangpatel]

/retest