fix unqiue name in handling forward slash (#1839)

Author: wing328

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

@@ -1609,7 +1609,7 @@ public String toApiName(String name) {
      * @return capitalized model name
      */
     public String toModelName(final String name) {
-        return initialCaps(modelNamePrefix + name + modelNameSuffix);
+        return initialCaps(modelNamePrefix + "_" + name + "_" + modelNameSuffix);
     }
 
     /**

modules/openapi-generator/src/main/java/org/openapitools/codegen/InlineModelResolver.java

@@ -420,6 +420,7 @@ private String uniqueName(String key) {
         }
         int count = 0;
         boolean done = false;
+        key = key.replaceAll("/", "_"); // e.g. /me/videos => _me_videos
         key = key.replaceAll("[^a-z_\\.A-Z0-9 ]", ""); // FIXME: a parameter
         // should not be assigned. Also declare the methods parameters as 'final'.
         while (!done) {