Fix typo (#11717)

Author: haider2122

core/src/main/java/org/testcontainers/containers/GenericContainer.java

@@ -1115,7 +1115,7 @@ public SELF withEnv(Map<String, String> env) {
     @Override
     public SELF withLabel(String key, String value) {
         if (key.startsWith("org.testcontainers")) {
-            throw new IllegalArgumentException("The org.testcontainers namespace is reserved for interal use");
+            throw new IllegalArgumentException("The org.testcontainers namespace is reserved for internal use");
         }
         this.containerDef.addLabel(key, value);
         return self();