lower ubtuntu back to 20.04

ubuntu latest kicks glibc up to 2.34

Author: zawata

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [macos-latest, windows-latest, ubuntu-latest]
+        os: [macos-latest, windows-latest, ubuntu-2004]
         arch: [x64, arm64]
         include:
           - os: macos-latest
@@ -34,7 +34,7 @@ jobs:
           - os: windows-latest
             friendlyName: Windows
             targetPlatform: win32
-          - os: ubuntu-latest
+          - os: ubuntu-2004
             friendlyName: Linux
             targetPlatform: ubuntu
         exclude:
@@ -71,12 +71,6 @@ jobs:
         run: |
           sudo apt-get update
           sudo apt-get install libcurl4-gnutls-dev libexpat1-dev gettext
-      - name: Install extra dependencies for building Git on Ubuntu (x86)
-        if: matrix.targetPlatform == 'ubuntu' && matrix.arch == 'x86'
-        run: |
-          sudo dpkg --add-architecture i386
-          sudo apt-get update
-          sudo apt-get install gcc-i686-linux-gnu binutils-i686-gnu libcurl4-gnutls-dev:i386 zlib1g-dev:i386 gettext
       - name: Install extra dependencies for building Git on Ubuntu (arm64)
         if: matrix.targetPlatform == 'ubuntu' && matrix.arch == 'arm64'
         run: |
@@ -86,15 +80,6 @@ jobs:
           sudo dpkg --add-architecture arm64
           sudo apt-get update
           sudo apt-get install gcc-aarch64-linux-gnu binutils-aarch64-linux-gnu libcurl4-gnutls-dev:arm64 zlib1g-dev:arm64 gettext
-      - name: Install extra dependencies for building Git on Ubuntu (arm)
-        if: matrix.targetPlatform == 'ubuntu' && matrix.arch == 'arm'
-        run: |
-          sudo sed -i "s/^deb/deb [arch=amd64,i386]/g" /etc/apt/sources.list
-          echo "deb [arch=arm64,armhf] http://azure.ports.ubuntu.com/ $(lsb_release -s -c) main universe multiverse restricted" | sudo tee -a /etc/apt/sources.list
-          echo "deb [arch=arm64,armhf] http://azure.ports.ubuntu.com/ $(lsb_release -s -c)-updates main universe multiverse restricted" | sudo tee -a /etc/apt/sources.list
-          sudo dpkg --add-architecture armhf
-          sudo apt-get update
-          sudo apt-get install gcc-arm-linux-gnueabihf binutils-arm-linux-gnueabihf libcurl4-gnutls-dev:armhf zlib1g-dev:armhf gettext
       - name: Build
         shell: bash
         run: script/build.sh