Review and update contributing guides

[michael-valdron]

Which area/kind this issue is related to?

/kind epic

Issue Description

Contributing guides in our repositories should be review and updated with the up to date information. Additionally, an investigation should be done to determine if a portion of the contributing guides should be centralized under devfile/api.

Contributing Guides

• devfile/api
• devfile/registry
• devfile/registry-support
• devfile/registry-operator
• devfile/devfile-web
• devfile/alizer
• devfile/library

Acceptance Criteria

• Spike: Review contributing guides and identify overlapping information #1353
• Review and update devfile/api contributing guide #1346
• Review and update devfile/registry contributing guide #1347
• Review and update devfile/registry-support contributing guide #1348
• Review and update devfile/registry-operator contributing guide #1349
• Review and update devfile/devfile-web contributing guide #1350
• Review and update devfile/alizer contributing guide #1351
• Review and update devfile/library contributing guide #1352

[michael-valdron]

/kind epic

Due to the size of the child stories and criteria this issue should be an epic.