[BUG][Workspace]Page crashed for invalid workspace color

[wanglam]

Describe the bug

The page crashed after create a workspace with an invalid workspace color. The workspace color will be used in EuiAvatar. It will show a error page when visit the workspace detail page.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Create workspace' page
2. Fill workspace name and select use case, input a invalid color.
3. Click on 'Create workspace' button
4. Page will redirect to workspace detail page
5. Page will show invalid color error

Expected behavior

1. Need to add validation on workspace color field, invalid value can't be saved in workspace create / update page
2. Invalid color value should not break the whole workspace detail page, it should render a default color.

OpenSearch Version
N/A

Dashboards Version
2.16

Plugins
N/A

Screenshots

Host/Environment (please complete the following information):
N/A

Additional context
#4944

[wanglam]

This bug has been fixed by #7671 , issue can be closed.