Changes

Runtime events: dispatch the right event message type (#13970)

* Dispatch the right event message type

`type.runtime | type.user` does not really make sense as `.runtime`
and `.user` are two projections of the same union type.

Prevents a MSVC 19.44.35109.1 warning:

    runtime/runtime_events.c(595): warning C5287: operands are different enum types
    'ev_runtime_message_type' and 'ev_user_message_type'; use an explicit cast to silence this warning

Co-authored-by: Gabriel Scherer <gabriel.scherer@gmail.com>

* Fit in 80 cols

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Co-authored-by: Gabriel Scherer <gabriel.scherer@gmail.com>
(cherry picked from commit 3e00aa54590360c0a97e471a259c5ad38ea12713)

Merge pull request #14102 from dra27/msvc-warnings

Address CI failures coming from recent GitHub Actions image updates

(cherry picked from commit 45e1a06ad69677e06d2110408ac414eeda10bf9f)