Hide create spaces button when limit is reached

[thomheymann]

Resolves #159028
Resolves #159047

Summary

Hide create spaces button when limit is reached.

Screenshot

Testing

1. Set the maximum number of allowed spaces to 1

xpack.spaces.maxSpaces: 1

2. Verify that the create spaces button is hidden and that a callout is displayed

[elasticmachine]

Pinging @elastic/kibana-security (Team:Security)

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: 8039833

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
spaces	174.8KB	173.7KB	-1.1KB

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
spaces	22.8KB	25.1KB	+2.3KB

Unknown metric groups

ESLint disabled line counts

id	before	after	diff
enterpriseSearch	19	21	+2
securitySolution	414	418	+4
total			+6

References to deprecated APIs

id	before	after	diff
spaces	13	10	-3

Total ESLint disabled count

id	before	after	diff
enterpriseSearch	20	22	+2
securitySolution	498	502	+4
total			+6

History

• 💚 Build #132973 succeeded 67006bf
• 💚 Build #132906 succeeded 75d5433
• 💔 Build #132859 failed 54a72e9

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@elasticmachine merge upstream

[jeramysoucy]

LGTM!