Fix EC integration tests CI: build weed binary and update actions

- Add 'Build weed binary' step before running tests
- Update actions/setup-go from v4 to v6 (Node20 compatibility)
- Update actions/checkout from v2 to v4 (Node20 compatibility)
- Move working-directory to test step only

.github/workflows/ec-integration-tests.yml

@@ -9,10 +9,6 @@ on:
 permissions:
   contents: read
 
-defaults:
-  run:
-    working-directory: test/erasure_coding
-
 jobs:
   ec-integration-tests:
     name: EC Integration Tests
@@ -20,15 +16,20 @@ jobs:
     timeout-minutes: 30
     steps:
     - name: Set up Go 1.x
-      uses: actions/setup-go@v4
+      uses: actions/setup-go@v6
       with:
         go-version: ^1.24
       id: go
 
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
+
+    - name: Build weed binary
+      run: |
+        cd weed && go build -o weed .
 
     - name: Run EC Integration Tests
+      working-directory: test/erasure_coding
       run: |
         go test -v