CI: Update ci_build.sh CMake to always make Unix Makefiles.

The default for many of the MSYS2 environments is for CMake to create
Ninja build files. This would complicate the build script since we would
need a different command to run the tests. Its simpler to always use
Unix Makefiles so that "make test" is always a usable target for
testing.

build-aux/ci_build.sh

@@ -236,8 +236,8 @@ then
 
 		# Remove old cache file to clear previous settings.
 		rm -f "CMakeCache.txt"
-		cmake "$SRC_DIR/CMakeLists.txt" -B "$DEST_DIR" $EXTRA_OPTIONS -DADDITIONAL_CHECK_TYPES="$CHECK_TYPE"
-		make
+		cmake "$SRC_DIR/CMakeLists.txt" -B "$DEST_DIR" $EXTRA_OPTIONS -DADDITIONAL_CHECK_TYPES="$CHECK_TYPE" -G "Unix Makefiles"
+		cmake --build "$DEST_DIR"
 	;;
 	esac
 fi