CI: Drop GCC-13

It seems to be missing in action in the ubuntu-22.04 container now.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>

Author: andyhhp

.github/workflows/build.yml

@@ -38,8 +38,6 @@ jobs:
             compiler: gcc-11
           - arch: x86
             compiler: gcc-12
-          - arch: x86
-            compiler: gcc-13
 
           - arch: x86
             compiler: clang-12