Document windows commands explicitly in the browser docs

[immavalls]

Based on https://community.k6.io/t/issue-using-k6-browser-unknown-module-k6-x-browser/6147/2?u=eyeveebe and some discussions I have had in the community slack (now https://community.k6.io/t/error-typeerror-value-is-not-an-object-undefined-when-i-run-the-example/6175), it would probably be good to document the Windows commands in the getting started guides explicitly.

https://k6.io/docs/javascript-api/k6-browser/get-started/running-browser-tests/

Instead of only:

Add the equivalents, similar to what we have in https://k6.io/docs/using-k6/environment-variables/#configure-k6-options-with-environment-variables.

Users getting started with the browser don't necessarily go to https://k6.io/docs/using-k6/environment-variables/#configure-k6-options-with-environment-variables

Alternatively mention that environment variables might be set differently based on the OS and link to https://k6.io/docs/using-k6/environment-variables/#configure-k6-options-with-environment-variables

[immavalls]

@MattDodsonEnglish What do you think about this one? Should we include different execution options (Bash, Windows, even docker?) on the getting started guides, or better point in the instructions to how to execute for different OS? I can fix this one once we decide what's best.

[mdcruz]

@immavalls I've quickly fixed this as part of #1078, as I did a few updates in the k6 browser documentation. Let me know if the change is okay :)

[immavalls]

Perfect @mdcruz Thanks!