chore: pin and update all workflow dependencies; add permission scopes (#2138)

---------

Signed-off-by: Christopher Phillips <christopher.phillips@anchore.com>

.github/workflows/update-bootstrap-tools.yml

@@ -9,14 +9,17 @@ env:
   GO_VERSION: "1.21.x"
   GO_STABLE_VERSION: true
 
+permissions:
+  contents: read
+
 jobs:
   update-bootstrap-tools:
     runs-on: ubuntu-latest
     if: github.repository == 'anchore/syft' # only run for main repo
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac #v4.0.0
 
-      - uses: actions/setup-go@v4
+      - uses: actions/setup-go@93397bea11091df50f3d7e59dc26a7711a8bcfbe #v4.1.0
         with:
           go-version: ${{ env.GO_VERSION }}
           stable: ${{ env.GO_STABLE_VERSION }}
@@ -55,13 +58,13 @@ jobs:
           echo "GLOW=GLOW_LATEST_VERSION" >> $GITHUB_OUTPUT
         id: latest-versions
 
-      - uses: tibdex/github-app-token@v2
+      - uses: tibdex/github-app-token@0914d50df753bbc42180d982a6550f195390069f #v2.0.0
         id: generate-token
         with:
           app_id: ${{ secrets.TOKEN_APP_ID }}
           private_key: ${{ secrets.TOKEN_APP_PRIVATE_KEY }}
 
-      - uses: peter-evans/create-pull-request@v5
+      - uses: peter-evans/create-pull-request@153407881ec5c347639a548ade7d8ad1d6740e38 #v5.0.2
         with:
           signoff: true
           delete-branch: true