License updates

[kim-tsao]

Please specify the area for this PR

What does does this PR do / why we need it:
This PR adds the following:

• license headers in go files
• license check to our workflow

Which issue(s) this PR fixes:

Fixes #?
devfile/api#931

PR acceptance criteria:

• Test Coverage
  • Are your changes sufficiently tested, and are any applicable test cases added or updated to cover your changes?

Documentation (WIP)

• Does the REST API doc need to be updated with your changes?
• Does the registry library doc need to be updated with your changes?

N/A
How to test changes / Special notes to the reviewer:

[codecov-commenter]

Codecov Report

Base: 43.46% // Head: 43.46% // No change to project coverage 👍

Coverage data is based on head (49ce947) compared to base (36887a7).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #140   +/-   ##
=======================================
  Coverage   43.46%   43.46%           
=======================================
  Files           6        6           
  Lines         971      971           
=======================================
  Hits          422      422           
  Misses        508      508           
  Partials       41       41           

Impacted Files	Coverage Δ
index/server/pkg/server/endpoint.go	35.25% <ø> (ø)
index/server/pkg/server/index.go	9.62% <ø> (ø)
index/server/pkg/server/registry.go	28.37% <ø> (ø)
index/server/pkg/util/filter.go	86.66% <ø> (ø)
index/server/pkg/util/telemetry.go	79.10% <ø> (ø)
index/server/pkg/util/util.go	63.63% <ø> (ø)

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[johnmcollier]

Looks good, just one suggestion

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: johnmcollier, kim-tsao

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• OWNERS [johnmcollier]

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