fix path to image in debug API page (#3858)

## Proposed changes

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### Reviewers: @webdriverio/technical-committee

packages/webdriverio/src/commands/browser/debug.js

@@ -7,7 +7,7 @@
  * interface that will allow you to try out certain commands, find elements and test actions on
  * them.
  *
- * [![WebdriverIO REPL](https://webdriver.io/images/repl.gif)](https://webdriver.io/images/repl.gif)
+ * [![WebdriverIO REPL](https://webdriver.io/img/repl.gif)](https://webdriver.io/img/repl.gif)
  *
  * If you run the WDIO testrunner make sure you increase the timeout property of the test framework
  * you are using (e.g. Mocha or Jasmine) in order to prevent test termination due to a test timeout.