Bump some Github actions (#2628)

Author: Quinn-With-Two-Ns

.github/workflows/gradle-wrapper-validation.yml

@@ -7,4 +7,4 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: gradle/actions/wrapper-validation@v3
+      - uses: gradle/actions/wrapper-validation@v4

.github/workflows/prepare-release.yml

@@ -139,7 +139,7 @@ jobs:
 
       # when no artifact is specified, all artifacts are downloaded and expanded into CWD
       - name: Fetch executables
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
 
       # example: linux_amd64/ -> temporal-test-server_1.2.3_linux_amd64
       # the name of the directory created becomes the basename of the archive (*.tar.gz or *.zip) and