Use camelCase for the driver extension command enumerations

[javifernandez]

This change has been discussed in the last meeting of the Web Driver WG during TPAC 2023 (Seville). For context, it's worth reading the previous discussion in the issue 175 and its resolution, reflected in the minutes of the meeting mentioned above:

jgraham: sounds like we have agreement on the first part that we need to adopt camel case

• At least two implementers are interested (and none opposed):
  • Mozilla supports it, as expressed in the meeting hold at TPAC
  • Google supports it, as expressed in the meeting hold at TPAC
• Tests are written and can be reviewed and commented upon at:
  • The PR 35792 under review to use the new RPH extension command
• Implementation bugs are filed:
  • Chromium: https://bugs.chromium.org/p/chromium/issues/detail?id=1359103
  • Gecko: https://bugzilla.mozilla.org/show_bug.cgi?id=1788789
• MDN issue is filed:
• The top of this comment includes a clear commit message to use.

(See WHATWG Working Mode: Changes for more details.)

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/system-state.html ( diff )

[annevk]

This looks reasonable. Please complete the checklist in OP and then we should be able to land this.