WADS, MAPS: sky texture revamp

[lavenderdotpet]

-- old versions of the pull req --
cleaned up these sky textures and removed an old/unfinished attempt at cleaning them up
sky_orng
sky_pando
sky_pando2

new version starts here ↓

Description of Changes

---

updated/cleaned up sky textures that i did in substance painter and edited in gimp

also some maps that used sky-test had the file replaced with the propper texture and sky-test was removed due to it breaking github auto build system as seen here #182 (comment)
the old versions of the skys were added to the legacy wad

Visual Sample

---

side note: also the last one there is just an extra now exists as sky_galx2 the old one is sky_galx

screenshot of maps using sky-test that i changed to the proper texture

Checklist

---

• I have read the LibreQuake contribution guidelines
• I have thoroughly tested my changes to the best of my ability
• I confirm I have not contributed anything that would impact LibreQuake's licensing and usage
• This Pull Request fixes a critical issue that should be reviewed and merged as soon as possible

[lavenderdotpet]

gonna work on this tonight

[lavenderdotpet]

[MotoLegacy]

In the future please follow our guidelines for commit messages

[lavenderdotpet]

In the future please follow our guidelines for commit messages

forgot that commits are under the same rules as pull reqs
my bad

[Nolcoz]

The new sky textures look really nice. Its good ye