Helm Chart: Add startupProbe to flower deployment

[MWatter]

Description

We've run into the issue of the flower pod not being quite ready by the time the readinessProbe starts firing leading to a crashbackoffloop. A startupProbe using the same check would be fairly painless and without significant side effects.

Use case/motivation

We would like to ensure that slow starting flower pods in our Airflow Helm deployments come into ready state cleanly.

Related issues

#33099 added startup probes to the scheduler and webserver.

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[boring-cyborg]

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