Cross-compile 32-bit on Ubuntu 22.04. This is a temporary change.

Ubuntu-latest has been moved to 24.04. That one uses GCC 13, which
is broken for 32-bit systems:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109504
This bug report says it's fixed in GCC 14. We'll wait for GitHub to
upgrade its GCC version.

.github/workflows/cmake.yml

@@ -40,7 +40,7 @@ jobs:
           - os: ubuntu-latest
             n_cores: 4
             wheel_location: pydip/staging/dist
-          - os: ubuntu-latest # cross-compile 32-bit
+          - os: ubuntu-22.04 # cross-compile 32-bit -- TEMPORARILY SET TO 22.04 because LATEST is now 24.04, with GCC-13, which is broken for 32-bit compilation
             cross_compile: true
             n_cores: 4
             dip_cmake_opts: -DCMAKE_C_FLAGS="-m32" -DCMAKE_CXX_FLAGS="-m32" -DDIP_BUILD_DIPVIEWER=Off -DDIP_BUILD_JAVAIO=Off -DDIP_BUILD_PYDIP=Off