Thiatt/v0.3.0/cors fix

[timbohiatt]

Description

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

This is primarily a bug fix in the local execution and development of containers locally.
The modification may look simple but actually took me days to fully understand. In development now an additional NGINX container in front of both the ShifterServer and ShifterUI containers. This NGINX container adds the CORS to the preflight requests allowing the two containers to call each other over localhost.

Fixes # (issue)

Primary Components Effected

Please mark one option with an "x".

• Shifter (Core CLI and Server Application)
• Shifter UI (The Web Interface)
• Cross Component Configuration (.github workflows, templates, docs, .MD files)

Type of change

Please mark one option with an "x".

• #RELEASE New Collection of Features (containing breaking and non-breaking changes)
• #FT New feature (non-breaking change which adds functionality)
• #BUG Bug Fix (non-breaking change which fixes an issue)
• #PATCH Patch (non-breaking change which modifies only non-code object [Docs, Readme])

Developer / Author Notes

Please feel free to provide any additional notes, content or context relating to this PR and subsequent contribution.

[timbohiatt]

@garybowers It took absolutely forever. But I think this is fixed once and for all....
CORS issue resolved for local execution. It should be okay now to go to v0.3.0. Please feel free to merge to v0.3.0 if it won't disturb any of your other branches. Ultimately it was really a minor change.