fish-shell: update to 3.6.4.

[akierig]

Testing the changes

• I tested the changes in this PR: YES

Local build testing

• I built this PR locally for my native architecture, x86_64
• I built this PR locally for these architectures (if supported. mark crossbuilds):
  • x86_64-musl

[triallax]

The release is just a test fix, is it worth the bump?

[akierig]

@mhmdanas is there a reason not to keep the versions in sync? Is there some big overhead i don't know about?

[triallax]

Nothing in particular, a rebuild just seems unnecessary to me, especially seeing as the tests are already passing for 3.6.3 on Void (#47574).

This is just my two cents though, it's not the end of the world if fish-shell is rebuilt :D