Replace invalid docker tag characters

[chatton]

Description

/ is not a valid docker tag character, this PR replaces any / values in git tags with - for docker tags to ensure they are valid.

this task builds an image for release/v5.0.x, the resulting tag is release-v5.0.x

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• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer
• Review Codecov Report in the comment section below once CI passes