FROST: Add github workflow to build with CMake

.github/workflows/build-with-cmake.yml

@@ -0,0 +1,84 @@
+name: Build using cmake
+
+# In secp256k1 some assertions are not exactly equal when coverage is enabled
+# and when it is not. Hence, it is better to run the two cases separately.
+
+on:
+  push:
+    branches:
+      - frost
+  pull_request:
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+  build-with-cmake:
+    runs-on: ubuntu-22.04
+    # Use fedora:38 to compile using gcc-13
+    container:
+      image: fedora:38
+    steps:
+      - name: Install build dependencies
+        run: |
+          dnf install -y \
+              autoconf \
+              automake \
+              gcc \
+              gcovr \
+              libtool \
+              pkg-config \
+              cmake
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 1
+      - name: Create and enter build directory
+        run: |
+          mkdir _build
+          cd _build
+      - name: Build with CMake
+        run: |
+          cmake \
+            -DCMAKE_C_FLAGS="-Werror" \
+            -DCMAKE_BUILD_TYPE="Release" \
+            -DSECP256K1_EXPERIMENTAL=ON \ 
+            -DSECP256K1_ENABLE_MODULE_FROST=ON \
+            -DSECP256K1_BUILD_BENCHMARK=OFF \
+            -DSECP256K1_BUILD_EXAMPLES=ON \ 
+            -DSECP256K1_BUILD_EXHAUSTIVE_TESTS=OFF \ 
+            -DSECP256K1_BUILD_TESTS=ON \
+             ..
+          cmake -- -j
+      - name: Run FROST example
+        continue-on-error: true
+        id: run_frost_example
+        run: |
+          ./examples/frost_example
+      - name: Functional tests with -Werror, no code coverage
+        continue-on-error: true
+        id: tests_no_coverage
+        run: |
+          ./src/tests
+      - name: Summarize outcomes. Fail if any step failed.
+        run: |
+          # summary
+          RED='\033[0;31m'
+          GREEN='\033[0;32m'
+          NC='\033[0m' # No Color
+
+          echo -n "FROST example: "
+          if [[ ${{ steps.run_frost_example.outcome }} == "success" ]]; then
+            printf "${GREEN}SUCCESS${NC}\n"
+          else
+            printf "${RED}FAIL${NC} (${{ steps.run_frost_example.outcome }}), please check\n"
+          fi
+          
+          echo -n "Functional tests with -Werror, no code coverage: "
+          if [[ ${{ steps.tests_no_coverage.outcome }} == "success" ]]; then
+            printf "${GREEN}SUCCESS${NC}\n"
+          else
+            printf "${RED}FAIL${NC} (${{ steps.tests_no_coverage.outcome }}), please check\n"
+          fi
+
+          if [[ ${{ steps.tests_with_coverage.outcome }} != "success" ]] || [[ ${{ steps.tests_no_coverage.outcome }} != "success" ]]; then
+            exit 1
+          fi