[CI] Fix GCC installation.

Author: vyazelenko

.github/workflows/ci.yml

@@ -176,7 +176,7 @@ jobs:
           key: ${{ runner.os }}-gradle-wrapper-${{ hashFiles('**/gradle/wrapper/gradle-wrapper.properties') }}
       - name: Install compiler
         run: |
-          sudo add-apt-repository ppa:ubuntu-toolchain-r/ppa
+          sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
           sudo apt-get update
           sudo apt-get install -y g++-${{ matrix.version }}
           curl -O -L https://github.com/Kitware/CMake/releases/download/v${CMAKE_VERSION}/cmake-${CMAKE_VERSION}-Linux-x86_64.tar.gz