SIG Content Guide should have information on acceptable dist tags, and explain overriding versions by appending Release

[NeilHanlon]

https://github.com/rocky-linux/wiki.rockylinux.org/blob/49f1dfd633639e714a9321541a290b824e0626f6/docs/special_interest_groups/sig_guide/content.md?plain=1#L75-L106 should have a section on Dist tags, and managing upgrade paths by appending to Release field (i.e., https://git.rockylinux.org/staging/patch/cloud-init/-/blob/r9/ROCKY/CFG/cloud-init.cfg#L11-14)

[NeilHanlon]

@nazunalika corrected me that we do have information on dist tags already. Let's take a pass at the build page and ensure it's accurate.

I'd also like to see if we can/should restrict this further in Peridot itself. We do some checking for if the project's dist tag has elN where N is the project's configured Major Version, but, it doesn't enforce that it starts with this, just that it contains it. Of course we can't make this too restrictive, but, we'll discuss that on the Peridot side.