Use SHAs for GHA versions

Per GitHub's security guidelines, GHAs should be pinned using full
length commit SHAs instead of tags.

The SHAs are of the commits currently resolved by the versions.

Even "trusted" GHAs from GitHub developers are pinned because it's
possible their repo rights could be compromised and a malicious GHA
published. These core repos are not frequently substantially updated.

Submariner-internal GHAs are left pinned at devel because we want
automatic updates from Shipyard's shared tooling.

Signed-off-by: Daniel Farrell <dfarrell@redhat.com>

.github/workflows/linting.yml

@@ -11,12 +11,12 @@ jobs:
     steps:
       - name: Get PR commits
         id: 'get-pr-commits'
-        uses: tim-actions/get-pr-commits@v1.1.0
+        uses: tim-actions/get-pr-commits@55b867b9b28954e6f5c1a0fe2f729dc926c306d0
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: 'Verify no "Apply suggestions from code review" commits'
-        uses: tim-actions/commit-message-checker-with-regex@v0.3.1
+        uses: tim-actions/commit-message-checker-with-regex@d6d9770051dd6460679d1cab1dcaa8cffc5c2bbd
         with:
           commits: ${{ steps.get-pr-commits.outputs.commits }}
           pattern: '^(?!.*(apply suggestions from code review))'
@@ -28,20 +28,20 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
 
       - name: Set up Helm
-        uses: azure/setup-helm@v1
+        uses: azure/setup-helm@18bc76811624f360dbd7f18c2d4ecb32c7b87bab
         with:
           version: v3.6.0
 
       - name: Set up Python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6
         with:
           python-version: '3.x'
 
       - name: Set up helm/chart-testing
-        uses: helm/chart-testing-action@v2.1.0
+        uses: helm/chart-testing-action@5f16c27cf7a4fa9c776ff73734df3909b2b65127
 
       - name: Run helm/chart-testing (lint)
         run: ct lint --config ct.yaml
@@ -51,7 +51,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
         with:
           fetch-depth: 0
       - name: Run gitlint
@@ -62,7 +62,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
 
       - name: Run helm-docs and verify docs are up-to-date
         run: make helm-docs
@@ -72,10 +72,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
 
       - name: Run markdown-link-check
-        uses: gaurav-nelson/github-action-markdown-link-check@v1
+        uses: gaurav-nelson/github-action-markdown-link-check@9710f0fec812ce0a3b98bef4c9d842fc1f39d976
         with:
           config-file: ".markdownlinkcheck.json"
           check-modified-files-only: "yes"
@@ -86,7 +86,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
       - name: Run markdownlint
         run: make markdownlint
 
@@ -95,9 +95,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out the repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
       - name: Run yamllint
-        uses: ibiqlik/action-yamllint@v1
+        uses: ibiqlik/action-yamllint@665205c3255fcf157ef8dc9a40d527fe025a4bc8
         with:
           file_or_dir: submariner-k8s-broker/Chart.yaml submariner-k8s-broker/values.yaml submariner-operator/Chart.yaml submariner-operator/values.yaml
           config_file: .yamllint.yml