Merge pull request #35 from Vlatombe/JENKINS-31166

[JENKINS-31166] Extra quotes messes up with environment variables content

src/main/java/com/cloudbees/jenkins/plugins/docker_build_env/Docker.java

@@ -305,7 +305,7 @@ public void executeIn(String container, String userId, Launcher.ProcStarter star
 
         // Build a list of environment, hidding node's one
         for (Map.Entry<String, String> e : environment.entrySet()) {
-            prefix.add(e.getKey()+"=\""+e.getValue()+'\"');
+            prefix.add(e.getKey()+"="+e.getValue());
         }
 
         starter.cmds().addAll(0, prefix);