Fix blinking regulation plot legend

Closes #2743

See merge request !3684

Resolve "typos in undulators doc"

Closes #2747

See merge request !3687

Emit a PrepareScanEvent

See merge request !3655

- This makes the plot legend blinking

Merge branch '1773-scan-engine-doesn-t-call-all-stops-if-an-exception-occured-in-on-stop' into 'master'

Resolve "Scan engine doesn't call all stops if an exception occured in on stop."

Closes #1773

See merge request !2553

fix issue #1773: ensure reading task is killed when acq. stop fails, to allow cleanup of all devices involved in the scan

Before the fix, if a `acq_stop` was failing, `wait_all_devices` was stuck
thus preventing cleaning up of other devices.

Resolve "test_failure: test_multi_top_master"

Closes #2741

See merge request !3678

Merge black constaints in the main requirement

Closes #2723

See merge request !3680

Resolve "Empty session reports errors in setup at startup"

Closes #2740

See merge request !3677

Release constraints on typeguard

Closes #1253

See merge request !3670

Demo: Fix lima simulators to use a resonable amount of memory

Closes #2734

See merge request !3668

Remove _scannable, use Scannable

Closes #2421

See merge request !3671

Set unit to CT2CounterTimer

Closes #1081

See merge request !3672

Resolve "typo in liboxford800 install documentation"

Closes #2716

See merge request !3674