Before this commit, contains() and its variants gave the client 3 seconds, and the bus helpers 2 seconds. The problem is that the first wait after openDiscuss pays for the whole mount, /mail/data and /discuss/channel/messages. Measured from openDiscuss resolving to the message being in the DOM:

- 250 to 460ms on an idle machine;
- 867 to 5258ms over 10 runs with the CPU throttled 4x, which is what a
  busy runbot looks like, 3 of the 10 over 2 seconds;
- 1474 to 6912ms with the CPU throttled 6x, 5 of 6 over 3 seconds.

"Reactions are ordered by id" fails 1 run in 60 at 4x for that reason.

Note that a longer timeout costs nothing on a green build: the timer is cleared as soon as the element is there, so it only delays the report of a test that was going to fail anyway.

This commit raises both to 10 seconds, the delay a tour step already gets in macro.js. test_js.py runs the presets with timeout=15000, so hoot fails the test itself at 15 seconds and 10 leaves room for the rest of the test.

This should also close most of the open runbot errors shaped like:

    Failed to find x of "..." (Timeout of 3 seconds). Found 0 instead.

The element does show up in those, just after the wait gave up.

https://runbot.odoo.com/odoo/error/944188

web companion https://github.com/odoo/odoo/pull/279984

Forward-Port-Of: odoo/odoo#280586
Forward-Port-Of: odoo/odoo#279983