Add cluster_tier flag support to Dataproc ClusterGenerator

[swainmoc]

This change adds a 'cluster_tier' flag to the ClusterGenerator, allowing users to specify the cluster tier during Dataproc cluster creation. This functionality is enabled by bumping the 'google-cloud-dataproc' pip package to version 5.21.0, which includes the necessary changes to support the new flag.

ClusterGenerator is an internal helper function that is used to generate cluster configs that is then used to pass to DataprocCreateClusterOperator dag (https://airflow.apache.org/docs/apache-airflow-providers-google/stable/operators/cloud/dataproc.html#generating-cluster-config)

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[boring-cyborg]

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[swainmoc]

Fail seems unrelated, some other version conflicts:

  241.5   × Failed to download and build `xmlsec==1.3.16`
  241.5   ╰─▶ Package metadata version `0.0.0` does not match given version `1.3.16`
  241.5   help: `xmlsec` (v1.3.16) was included because
  241.5         `apache-airflow-providers-amazon[python3-saml]` (v9.12.0) depends
  241.5         on `xmlsec`

[Lee-W]

Fail seems unrelated, some other version conflicts:

  241.5   × Failed to download and build `xmlsec==1.3.16`
  241.5   ╰─▶ Package metadata version `0.0.0` does not match given version `1.3.16`
  241.5   help: `xmlsec` (v1.3.16) was included because
  241.5         `apache-airflow-providers-amazon[python3-saml]` (v9.12.0) depends
  241.5         on `xmlsec`

I think it has been fixed on the main branch. Rebase from the main branch and retry might fix it

[swainmoc]

@Lee-W Can you re-run the tests

[swainmoc]

@Lee-W can we merge 🚀

[Lee-W]

Let's wait for one or two days in case someone wants to take another look :) Will merge it then. Thanks for making airflow better!

[Lee-W]

time to merge it 🚀

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.