QE: Add extra wait for Grafana to load in BV

[vandabarata]

What does this PR change?

Adds an extra wait to account for the time between the Loading text disappearing and the options for dashboards to appear. "General" is a section that always appears when loading is done.

Links

• 4.2 https://github.com/SUSE/spacewalk/pull/22329

• 4.3 https://github.com/SUSE/spacewalk/pull/22328

• DONE

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