Fix Firefox CI issue (#6833)

Author: hsubox76

.github/workflows/test-changed-auth.yml

@@ -38,7 +38,10 @@ jobs:
         run: xvfb-run yarn test:changed auth
   test-firefox:
     name: Test Auth on Firefox If Changed
-    runs-on: ubuntu-latest
+    # Whatever version of Firefox comes with 22.04 is causing Firefox
+    # startup to hang when launched by karma. Need to look further into
+    # why.
+    runs-on: ubuntu-20.04
 
     steps:
       - name: install Firefox stable

.github/workflows/test-changed-firestore.yml

@@ -34,7 +34,10 @@ jobs:
 
   test-firefox:
     name: Test Firestore on Firefox If Changed
-    runs-on: ubuntu-latest
+    # Whatever version of Firefox comes with 22.04 is causing Firefox
+    # startup to hang when launched by karma. Need to look further into
+    # why.
+    runs-on: ubuntu-20.04
 
     steps:
       - name: install Firefox stable

.github/workflows/test-changed.yml

@@ -34,7 +34,10 @@ jobs:
 
   test-firefox:
     name: Test Packages With Changed Files in Firefox
-    runs-on: ubuntu-latest
+    # Whatever version of Firefox comes with 22.04 is causing Firefox
+    # startup to hang when launched by karma. Need to look further into
+    # why.
+    runs-on: ubuntu-20.04
 
     steps:
       - name: Checkout Repo