Mention upgrade with Terraform/OpenTofu provider for Flux in release notes

[mloskot]

I noticed, Flux release notes like this for 2.4.0 include the note on upgrade procedure:

Upgrade Flux from v2.3.0 to v2.4.0 either by rerunning bootstrap or by using the Flux GitHub Action.

Would it be possible to also mention the https://github.com/fluxcd/terraform-provider-flux/ as an additional viable upgrade option?

I have been using the provider for Flux for quite some time now and successfully performed numerous upgrades, and easily.
I think, it is quite important to make it clear to the provider users that they can use it to upgrade the Flux deployment.

[stefanprodan]

We should link to the upgrade docs here which captures all options including Terraform https://fluxcd.io/flux/installation/upgrade/

[mloskot]

@stefanprodan That would do indeed. I thought of submitting PR updating this section

flux2/docs/release/release-notes-template.md

Lines 46 to 49 in 5b83111

	In some scenarios, you may want to include specific information about API
	changes and/or upgrade procedures. Consult [the formatting of
	`v2.0.0-rc.1`](https://github.com/fluxcd/flux2/releases/tag/v2.0.0-rc.1) for
	such an example.

but I feel like this is too internal content to be modified by someone from outside like myself. I don't even know if this template is still in use.

[stefanprodan]

It’s usually me that writes the release notes. You can open a PR for the template, thanks!

[mloskot]

Done in #5073 Thank you!