sfp impact releaseconfig with filterByChangesInBranch option use tag for package descriptor diff

[alanjaouen]

Describe the bug When using sfp impact releaseconfig --releaseconfig=releases/definitions --filterByChangesInBranch --basebranch=main --branch=HEAD with no changes in branch, commands return impacted packages.

To Reproduce

• change package descriptor in basebranch.
• create a branch from basebranch
• sfp impact releaseconfig

Expected behavior When using filterByChangesInBranch option, package descriptor should not be diff against latest tag

Platform Details (please complete the following information):

• OS: windows
• Version [e.g. CLI Version eg: 1.6.6] : 39.2.2
• Salesforce CLI(sfdx cli) Version: @salesforce/cli/2.60.13 win32-x64 node-v20.17.0

[azlam-abdulsalam]

@alanjaouen Checking into this and thanks for the PR