Apply suggestions from code review

Co-authored-by: Sutou Kouhei <kou@cozmixng.org>

Author: lidavidm

.github/workflows/java.yml

@@ -53,12 +53,12 @@ jobs:
       MAVEN: ${{ matrix.maven }}
     steps:
       - name: Checkout Arrow
-        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
+        uses: actions/checkout@eef61447b9ff4aafe5dcd4e0bbf5d482be7e7871 # v4.2.1
         with:
           fetch-depth: 0
           submodules: recursive
       - name: Cache Docker Volumes
-        uses: actions/cache@13aacd865c20de90d75de3b17ebe84f7a17d57d2 # v4.0.0
+        uses: actions/cache@6849a6489940f00c2f30c0fb92c6274307ccb58a # v4.1.2
         with:
           path: .docker
           key: maven-${{ hashFiles('java/**') }}

.gitmodules

@@ -1,3 +1,3 @@
 [submodule "testing"]
 	path = testing
-	url = git@github.com:apache/arrow-testing
+	url = https://github.com/apache/arrow-testing.git