feat(rum-explorer): select all when focusing the input field, so that new value can be typed instantly

[aem-code-sync[bot]]

Hello, I'm the AEM Code Sync Bot and I will run some actions to deploy your branch and validate page speed. In case there are problems, just click a checkbox below to rerun the respective action.

• [ ] Re-run PSI checks
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Commits

* [63d81ed](https://github.com/adobe/helix-website/commit/63d81ed7d081d39895fc82f96b233269a68809bc) :white_check_mark: (latest) * [cc445c9](https://github.com/adobe/helix-website/commit/cc445c97e05c51c4ddf0c9af8c9119f7dced3985) :white_check_mark: