Add go mod download step to CI jobs to fix proxy.golang.org 403 errors (#12976)

Author: Copilot

.github/workflows/ci.yml

@@ -38,6 +38,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -190,6 +193,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -296,6 +302,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -480,6 +489,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -648,6 +660,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -719,6 +734,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -756,6 +774,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -847,6 +868,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -1204,6 +1228,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify
 
@@ -1301,6 +1328,9 @@ jobs:
             echo "⚠️ Go cache miss" >> $GITHUB_STEP_SUMMARY
           fi
 
+      - name: Download dependencies
+        run: go mod download
+
       - name: Verify dependencies
         run: go mod verify