Test git client plugin master branch with 2.48.0 test fix

CLI git 2.48.0 changed a minor behavior that was unintentionally being
checked by the tests in the git client plugin.  The git client plugin
test has been modified to adapt to the behavior of CLI git 2.48.0 and
later.

bom-weekly/pom.xml

@@ -957,7 +957,9 @@
       <dependency>
         <groupId>org.jenkins-ci.plugins</groupId>
         <artifactId>git-client</artifactId>
-        <version>6.1.1-rc3667.8f7cddc42e9e</version>
+        <!-- master branch after adapting test for CLI git 2.48.0 -->
+        <!-- https://github.com/jenkinsci/git-client-plugin/commit/8d5f9c37c25ece914f7d968efda9bdf36ad74aab -->
+        <version>6.1.1-rc3667.8d5f9c37c25e</version>
       </dependency>
       <dependency>
         <groupId>org.jenkins-ci.plugins</groupId>