Fixed var in CI call

Author: Hish15

.github/workflows/cmake.yml

@@ -62,7 +62,7 @@ jobs:
       run: |
         FAMILY_LOWER=$(echo "${{ matrix.family }}" | tr '[:upper:]' '[:lower:]')
         RELATIVE_PATH="../../cmsis/build-relative/_deps/stm32cube${FAMILY_LOWER}-src"
-        cmake -DTEST_FAMILIES=${{ matrix.family }} -DSTM32_CUBE_${{ matrix.family }}_PATH=${RELATIVE_PATH} $GITHUB_WORKSPACE/tests/cmsis/
+        cmake -DTEST_FAMILIES=${{ matrix.family }} -DSTM32_CUBE_${{ matrix.family }}_PATH="${RELATIVE_PATH}" "$GITHUB_WORKSPACE/tests/cmsis/"
       if: ${{ matrix.family != 'MP1' }}
 
     - name: Build tests/cmsis with relative path