typescript-fetch: Fix two spaces after get headers()

Created by: JoshuaKGoldberg

This is a very small change and not at all important: there are two spaces after get header(): instead of just the normal one.

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@leonyu

modules/openapi-generator/src/main/resources/typescript-fetch/runtime.mustache

@@ -172,7 +172,7 @@ export class Configuration {
         return undefined;
     }
 
-    get headers():  HTTPHeaders | undefined {
+    get headers(): HTTPHeaders | undefined {
         return this.configuration.headers;
     }
 

samples/client/petstore/typescript-fetch/builds/default/runtime.ts

@@ -183,7 +183,7 @@ export class Configuration {
         return undefined;
     }
 
-    get headers():  HTTPHeaders | undefined {
+    get headers(): HTTPHeaders | undefined {
         return this.configuration.headers;
     }
 

samples/client/petstore/typescript-fetch/builds/default-v3.0/runtime.ts

@@ -183,7 +183,7 @@ export class Configuration {
         return undefined;
     }
 
-    get headers():  HTTPHeaders | undefined {
+    get headers(): HTTPHeaders | undefined {
         return this.configuration.headers;
     }
 

samples/client/petstore/typescript-fetch/builds/enum/runtime.ts

@@ -183,7 +183,7 @@ export class Configuration {
         return undefined;
     }
 
-    get headers():  HTTPHeaders | undefined {
+    get headers(): HTTPHeaders | undefined {
         return this.configuration.headers;
     }
 

samples/client/petstore/typescript-fetch/builds/es6-target/src/runtime.ts

@@ -183,7 +183,7 @@ export class Configuration {
         return undefined;
     }
 
-    get headers():  HTTPHeaders | undefined {
+    get headers(): HTTPHeaders | undefined {
         return this.configuration.headers;
     }