chore(ci): Update builder image

Author: epage

.github/workflows/post-release.yml

@@ -61,7 +61,7 @@ jobs:
         build: [linux, macos, win-msvc]
         include:
         - build: linux
-          os: ubuntu-20.04
+          os: ubuntu-22.04
           rust: stable
           target: x86_64-unknown-linux-gnu
         - build: macos
@@ -79,7 +79,7 @@ jobs:
       with:
         fetch-depth: 1
     - name: Install packages (Ubuntu)
-      if: matrix.os == 'ubuntu-20.04'
+      if: matrix.os == 'ubuntu-22.04'
       run: |
         sudo apt-get update
         sudo apt-get install -y --no-install-recommends xz-utils liblz4-tool