Workaround electron/forge#3102.

Downgrade GitHub-hosted Linux runner to `ubuntu-20.04`.

Author: SpacingBat3

.github/workflows/build.yml

@@ -63,18 +63,18 @@ jobs:
         runner: [ubuntu, windows, macos]
         build: [latest, locked]
         include:
-          - runner: ubuntu
+          - runner: ubuntu-20.04
             name: Linux
             arch: x64,arm64,armv7l
-          - runner: windows
+          - runner: windows-latest
             name: Windows
             arch: x64,arm64,ia32
-          - runner: macos
+          - runner: macos-latest
             name: macOS
             arch: x64,arm64,universal
 
     name: '${{ matrix.name }} (${{ matrix.build }})'
-    runs-on: ${{ matrix.runner }}-latest
+    runs-on: ${{ matrix.runner }}
     needs: ['test']
     steps:
       - uses: actions/checkout@v3

.github/workflows/prerelease.yml

@@ -15,17 +15,17 @@ jobs:
       matrix:
         include:
           - name: Linux
-            runner: ubuntu
+            runner: ubuntu-20.04
             arch: x64,arm64,armv7l
           - name: Windows
-            runner: windows
+            runner: windows-latest
             arch: x64,arm64,ia32
           - name: macOS
-            runner: macos
+            runner: macos-latest
             arch: x64,arm64,universal
 
     name: ${{ matrix.name }} (${{ matrix.arch }})
-    runs-on: ${{ matrix.runner }}-latest
+    runs-on: ${{ matrix.runner }}
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3

.github/workflows/release.yml

@@ -15,17 +15,17 @@ jobs:
       matrix:
         include:
           - name: Linux
-            runner: ubuntu
+            runner: ubuntu-20.04
             arch: x64,arm64,armv7l
           - name: Windows
-            runner: windows
+            runner: windows-latest
             arch: x64,arm64,ia32
           - name: macOS
-            runner: macos
+            runner: macos-latest
             arch: x64,arm64,universal
 
     name: ${{ matrix.name }} (${{ matrix.arch }})
-    runs-on: ${{ matrix.runner }}-latest
+    runs-on: ${{ matrix.runner }}
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3