Update generic_event.rst

The $event['data'] field was not set, thus it wouldn't be modified.

Also, the example already had a lowercase string. Uppercased 1 letter.
bug #3541 Update generic_event.rst (Lumbendil)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #3541).

Discussion
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Update generic_event.rst

The $event['data'] field was not set, thus it wouldn't be modified.

Also, the example already had a lowercase string. Uppercased 1 letter.

Commits
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029f4e1 Update generic_event.rst