Before this commit, the loading indicator is shown immediately after
each network request. But this is distracting, and may cause an
impression of slowness, since it shows that the web client is working.
However, the feedback is very useful.
So, it has been decided that we would only display the loading indicater
after a delay of 250ms. All requests shorter than that duration will
just not show anything.
closesodoo/odoo#95037
Task: 2900450
Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>