Simplify build workflow

Rename it from "Compilation" to "Build", as it's shorter and takes less
space in GitHub UI.

Remove GCC8 build configuration, as it does not add value: GCC9
build provides compilation on new compiler, while other Ubuntu builds
cover compilation on default compilers.

.github/workflows/build.yml

@@ -1,4 +1,4 @@
-name: Compilation
+name: "Build"
 
 on: [push]
 
@@ -12,7 +12,7 @@ jobs:
       - run: sudo apt update
       - name: "Install packages"
         run: sudo apt-get install g++-9 libsdl1.2-dev libsdl-net1.2-dev libsdl-sound1.2-dev
-      - name: Build
+      - name: "Build"
         env:
           CC: gcc-9
           CXX: g++-9
@@ -23,32 +23,10 @@ jobs:
           ./autogen.sh
           ./configure CXXFLAGS="-Wall -fdiagnostics-color=always"
           make -j "$(nproc)" |& tee build.log
-      - name: Summarize warnings
+      - name: "Summarize warnings"
         run: python3 ./scripts/count-warnings.py build.log
 
-  build_gcc8:
-    name: "GCC 8 (ubuntu-18.04)"
-    runs-on: ubuntu-18.04
-    steps:
-      - uses: actions/checkout@v1
-      - run: sudo apt update
-      - name: "Install packages"
-        run: sudo apt-get install g++-8 libsdl1.2-dev libsdl-net1.2-dev libsdl-sound1.2-dev
-      - name: Build
-        env:
-          CC: gcc-8
-          CXX: g++-8
-        run: |
-          # build steps
-          set -x
-          $CXX --version
-          ./autogen.sh
-          ./configure CXXFLAGS="-Wall -fdiagnostics-color=always"
-          make -j "$(nproc)" |& tee build.log
-      - name: Summarize warnings
-        run: python3 ./scripts/count-warnings.py build.log
-
-  build_ubuntu:
+  build_gcc_ubuntu:
     name: "GCC"
     runs-on: ${{ matrix.os }}
     strategy:
@@ -59,7 +37,7 @@ jobs:
       - run: sudo apt update
       - name: "Install packages"
         run: sudo apt-get install libsdl1.2-dev libsdl-net1.2-dev libsdl-sound1.2-dev
-      - name: Build
+      - name: "Build"
         run: |
           # build steps
           set -x
@@ -67,18 +45,18 @@ jobs:
           ./autogen.sh
           ./configure CXXFLAGS="-Wall -fdiagnostics-color=always"
           make -j "$(nproc)" |& tee build.log
-      - name: Summarize warnings
+      - name: "Summarize warnings"
         run: python3 ./scripts/count-warnings.py build.log
 
   build_clang:
-    name: "Clang 6 (ubuntu-18.04)"
+    name: "Clang (ubuntu-18.04)"
     runs-on: ubuntu-18.04
     steps:
       - uses: actions/checkout@v1
       - run: sudo apt update
       - name: "Install packages"
         run: sudo apt-get install libsdl1.2-dev libsdl-net1.2-dev libsdl-sound1.2-dev
-      - name: Build
+      - name: "Build"
         env:
           CC: clang
           CXX: clang++
@@ -89,7 +67,7 @@ jobs:
           ./autogen.sh
           ./configure CXXFLAGS="-Wall"
           make -j "$(nproc)" |& tee build.log
-      - name: Summarize warnings
+      - name: "Summarize warnings"
         run: python3 ./scripts/count-warnings.py build.log
 
   build_macos:
@@ -100,7 +78,7 @@ jobs:
       - run: brew update
       - name: "Install packages"
         run: brew install automake libpng sdl sdl_net sdl_sound
-      - name: Build
+      - name: "Build"
         run: |
           # build steps
           set -x
@@ -108,5 +86,5 @@ jobs:
           ./autogen.sh
           ./configure CXXFLAGS="-Wall"
           make -j "$(sysctl -n hw.physicalcpu)" 2>&1 | tee build.log
-      - name: Summarize warnings
+      - name: "Summarize warnings"
         run: python3 ./scripts/count-warnings.py build.log