docs: fix indentation in configuration page

Author: mrlubos

docs/openapi-ts/configuration.md

@@ -161,7 +161,7 @@ export default [
 ];
 ```
 
-```md [example]
+```txt [example]
 src/
 ├── foo/
 │ ├── client/
@@ -171,12 +171,12 @@ src/
 │ ├── sdk.gen.ts
 │ └── types.gen.ts
 └── bar/
-├── client/
-├── core/
-├── client.gen.ts
-├── index.ts
-├── sdk.gen.ts
-└── types.gen.ts
+  ├── client/
+  ├── core/
+  ├── client.gen.ts
+  ├── index.ts
+  ├── sdk.gen.ts
+  └── types.gen.ts
 ```
 
 :::
@@ -194,7 +194,7 @@ export default {
 };
 ```
 
-```md [example]
+```txt [example]
 src/
 ├── foo/
 │ ├── client/
@@ -204,12 +204,12 @@ src/
 │ ├── sdk.gen.ts
 │ └── types.gen.ts
 └── bar/
-├── client/
-├── core/
-├── client.gen.ts
-├── index.ts
-├── sdk.gen.ts
-└── types.gen.ts
+  ├── client/
+  ├── core/
+  ├── client.gen.ts
+  ├── index.ts
+  ├── sdk.gen.ts
+  └── types.gen.ts
 ```
 
 :::
@@ -227,15 +227,15 @@ export default {
 };
 ```
 
-```md [example]
+```txt [example]
 src/
 └── client/
-├── client/
-├── core/
-├── client.gen.ts
-├── index.ts
-├── sdk.gen.ts
-└── types.gen.ts
+  ├── client/
+  ├── core/
+  ├── client.gen.ts
+  ├── index.ts
+  ├── sdk.gen.ts
+  └── types.gen.ts
 ```
 
 :::

docs/openapi-ts/output.md

@@ -11,7 +11,7 @@ Every generated file in your output folder is created by a plugin. This page des
 
 If you use the default configuration, your [project](https://stackblitz.com/edit/hey-api-example?file=openapi-ts.config.ts,src%2Fclient%2Fschemas.gen.ts,src%2Fclient%2Fsdk.gen.ts,src%2Fclient%2Ftypes.gen.ts) might look like this.
 
-```md
+```txt
 my-app/
 ├── node_modules/
 ├── src/