Update Devfile Registry Support Services to use Go 1.19

[michael-valdron]

Which area/kind this issue is related to?

/area registry

Issue Description

To meet the objective of #1237, we need to ensure our registry support services is using Go 1.19 with updated dependencies.

Acceptance Criteria

• [x] Update index/generator/go.mod to use Go 1.19
• [x] Update index/server/go.mod to use Go 1.19
• [x] Update registry-library/go.mod to use Go 1.19
• [x] Update tests/integration/go.mod to use Go 1.19
• [x] Update dependencies under index/generator/go.mod and index/generator/go.sum and migrate any changes
• [x] Update dependencies under index/server/go.mod and index/server/go.sum and migrate any changes
• [x] Update dependencies under registry-library/go.mod and registry-library/go.sum and migrate any changes
• [x] Update dependencies under tests/integration/go.mod and tests/integration/go.sum and migrate any changes
• [X] Refactor all library calls to io/ioutil since it is now deprecated
• [x] Update workflows to use Go 1.19
• [x] Update requirements under documentation

[michael-valdron]

Update requirements under documentation

No prior documentation in registry-support on Go version requirements, added a Go version badge to the root README.

[michael-valdron]

Go 1.19 changes are for ready for review: https://github.com/devfile/registry-support/pull/212

[michael-valdron]

Need to merge https://github.com/devfile/registry/pull/316 before merging https://github.com/devfile/registry-support/pull/212.

[michael-valdron]

PR update: https://github.com/devfile/registry-support/pull/212#issuecomment-1985978987