2212/ensure that create cluster button is visible [helix-front]

[micahstubbs]

Issues

• My PR addresses the following Helix issues and references them in the PR description:

Fix #2212

Description

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This PR ensures that the create cluster button is visible in the left sidebar in the cluster list view. This is done both by updating styles as well as by verifying that the current user is logged in after loading all clusters.

Tests

• The following tests are written for this issue:

Commits

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Code Quality

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[micahstubbs]

This PR is ready to be merged, approved by @somecodemonkey
Final commit message:

Ensure that create cluster button is visible [helix-front] (#2212)

Verify that current user is logged in after loading all clusters
to ensure that create cluster button is visible in left sidebar