chore(E2E test README): Add steps for adding IDE e2e build tags (#3761)

Co-authored-by: Jorge Turrado Ferrero <Jorge_turrado@hotmail.es>

tests/README.md

@@ -43,6 +43,19 @@ in parallel, but tests within a file can be run in parallel or in series. More a
 
 - **Global cleanup:** This is done in [`utils/cleanup_test.go`](utils/cleanup_test.go). It cleans up all the resources created in `utils/setup_test.go`.
 
+> **Note**
+> Your IDE might give you errors upon trying to import certain packages that use the `e2e` build tag. To overcome this, you will need to specify in your IDE settings to use the `e2e` build tag.
+>
+> As an example, in VSCode, it can be achieved by creating a `.vscode` directory within the project directory (if not present) and creating a `settings.json` file in that directory (or updating it) with the following content:
+> ```json
+> {
+>   "go.buildFlags": [
+>       "-tags=e2e"
+>   ],
+>   "go.testTags": "e2e",
+> }
+> ```
+
 ## Adding tests
 
 - Tests are written using `Go`'s default [`testing`](https://pkg.go.dev/testing) framework, and [`testify`](https://pkg.go.dev/github.com/stretchr/testify).