brl-fetch: add development releases of fedora

[CactiChameleon9]

This PR should fix the default release being from testing issue (sorry for the 2nd pr)

I am unsure on how to show the releases, so feedback and corrections wanted there
I also hope using tr is alright
And yes, fetching the fedora development releases multiple times does add on a bit of time, however it seemed to match the coding style more than using a global variable and fedora takes a while to fetch anyway (so not loads % wise)

[CactiChameleon9]

I just noticed a small issue with fetching rawhide (it still fetches fine):

[13/20 ( 65%)] Running bootstrap software
Unable to detect release version (use '--releasever' to specify release version)
Fedora $releasever openh264 (From   19 kB/s |  92 kB     00:04    
Errors during downloading metadata for repository 'fedora-cisco-openh264':
  - Status code: 404 for https://mirrors.fedoraproject.org/metalink?repo=fedora-cisco-openh264-$releasever&arch=x86_64 (IP: 209.132.190.2)
  - Status code: 404 for https://mirrors.fedoraproject.org/metalink?repo=fedora-cisco-openh264-$releasever&arch=x86_64 (IP: 38.145.60.20)
  - Status code: 404 for https://mirrors.fedoraproject.org/metalink?repo=fedora-cisco-openh264-$releasever&arch=x86_64 (IP: 18.185.136.17)
Error: Failed to download metadata for repo 'fedora-cisco-openh264': Cannot prepare internal mirrorlist: Status code: 404 for https://mirrors.fedoraproject.org/metalink?repo=fedora-cisco-openh264-$releasever&arch=x86_64 (IP: 18.185.136.17)
Ignoring repositories: fedora-cisco-openh264
Last metadata expiration check: 1:01:16 ago on Tue Mar  8 01:20:47 2022.

I am attempting to resolve it now