.github: Update version comments

Signed-off-by: Stephen Augustus (he/him) <[email protected]>

Author: justaugustus

.github/workflows/tests.yaml

@@ -19,7 +19,7 @@ jobs:
     steps:
       - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b #v2.4.0
         # https://github.com/mvdan/github-actions-golang#how-do-i-set-up-caching-between-builds
-      - uses: actions/cache@fd5de65bc895cf536527842281bea11763fefd77 #v2.1.7
+      - uses: actions/cache@fd5de65 # 3.0.z
         with:
           # In order:
           # * Module download cache
@@ -55,7 +55,7 @@ jobs:
     steps:
       - uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b #v2.4.0
         # https://github.com/mvdan/github-actions-golang#how-do-i-set-up-caching-between-builds
-      - uses: actions/cache@fd5de65bc895cf536527842281bea11763fefd77 #v2.1.7
+      - uses: actions/cache@fd5de65 # 3.0.z
         with:
           # In order:
           # * Module download cache