docs(integration-examples): add badge showing what version the example is for

Author: hasezoey

docs/guides/integration-examples.md

@@ -7,6 +7,8 @@ This Guide will show how `mongodb-memory-server` can be used with different fram
 
 ## jest
 
+<span class="badge badge--secondary">jest version 27</span>
+
 For useage with `jest` it is recommended to use the [`globalSetup`](https://jestjs.io/docs/en/configuration#globalsetup-string) and [`globalTeardown`](https://jestjs.io/docs/en/configuration#globalteardown-string) options
 
 `jest.config.json`:
@@ -86,6 +88,8 @@ Use [`--maxWorkers 4`](https://jestjs.io/docs/configuration#maxworkers-number--s
 
 ## mocha / chai
 
+<span class="badge badge--secondary">mocha version (unknown)</span>
+
 Start Mocha with `--timeout 60000` cause first download of MongoDB binaries may take a time.
 
 ```js