Login to DockerHub prior to checking out code. (#2750)

This prevents the "Login to DockerHub" step from confusing the image tag name. At the moment the containers are incorrectly named "v1.7.0-devel-wip".

.github/workflows/publish-alloy-devel.yml

@@ -15,6 +15,13 @@ jobs:
     runs-on:
       labels: github-hosted-ubuntu-x64-large
     steps:
+      # This step needs to run before "Checkout code".
+      # That's because it generates a new file.
+      # We don't want this file to end up in the repo directory.
+      # Then "tools/image-tag" would get confused because "git status" no longer reports a clean repo.
+    - name: Login to DockerHub (from vault)
+      uses: grafana/shared-workflows/actions/[email protected]
+
     - name: Checkout code
       uses: actions/checkout@v4
 
@@ -30,9 +37,6 @@ jobs:
         go-version-file: go.mod
         cache: false
 
-    - name: Login to DockerHub (from vault)
-      uses: grafana/shared-workflows/actions/[email protected]
-
     - run: |
        docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
        docker buildx create --name multiarch-alloy-alloy-devel-${GITHUB_SHA} --driver docker-container --use
@@ -45,6 +49,13 @@ jobs:
     runs-on:
       labels: github-hosted-ubuntu-x64-large
     steps:
+    # This step needs to run before "Checkout code".
+    # That's because it generates a new file.
+    # We don't want this file to end up in the repo directory.
+    # Then "tools/image-tag" would get confused because "git status" no longer reports a clean repo.
+    - name: Login to DockerHub (from vault)
+      uses: grafana/shared-workflows/actions/[email protected]
+
     - name: Checkout code
       uses: actions/checkout@v4
 
@@ -60,9 +71,6 @@ jobs:
         go-version-file: go.mod
         cache: false
 
-    - name: Login to DockerHub (from vault)
-      uses: grafana/shared-workflows/actions/[email protected]
-
     - run: |
        docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
        docker buildx create --name multiarch-alloy-alloy-devel-boringcrypto-${GITHUB_SHA} --driver docker-container --use