Configurable RequeueDelay

[addreas]

Description

Allows the current default of refreshing dashboards every 10 seconds to be configured. This might be useful in the situation where something isn't configured correctly, or there are a huge amount of dashboards such that the operator is constantly busy updating dashboards which might make it hard to understand what is happening.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• This change requires a documentation update
• I have added tests that prove my fix is effective or that my feature works
• I have added a test case that will be used to verify my changes
• Verified independently on a cluster by reviewer

Verification steps

Tested on a home cluster and seems to work as intended.

[NissesSenap]

@addreas I took a quick check and i think it's a great idea and should have probably been the case from the get go but you learn every day.

Could you write something about it in the docs?
I guess https://github.com/grafana-operator/grafana-operator/blob/master/documentation/deploy_grafana.md#operator-flags is the place to put it.

[NissesSenap]

@addreas I took the liberty of writing a small mention about this in the docs since I really wanted this feature in the new release.
Thanks for your great contributions!