Use constant for no_proxy key

Author: roamingthings

modules/selenium/src/main/java/org/testcontainers/containers/BrowserWebDriverContainer.java

@@ -44,6 +44,8 @@ public class BrowserWebDriverContainer<SELF extends BrowserWebDriverContainer<SE
     private static final int SELENIUM_PORT = 4444;
     private static final int VNC_PORT = 5900;
 
+    private static final String NO_PROXY_KEY = "no_proxy";
+
     @Nullable
     private DesiredCapabilities desiredCapabilities;
     private boolean customImageNameIsSet = false;
@@ -132,8 +134,8 @@ protected void configure() {
         addExposedPorts(SELENIUM_PORT, VNC_PORT);
         addEnv("TZ", timeZone);
 
-        if (!getEnvMap().containsKey("no_proxy")) {
-            addEnv("no_proxy", "localhost");
+        if (!getEnvMap().containsKey(NO_PROXY_KEY)) {
+            addEnv(NO_PROXY_KEY, "localhost");
         }
 
         setCommand("/opt/bin/entry_point.sh");