Squashed 'external/devlib/' changes from 7866086ec..1196e336a

1196e336a version: bump minor version number
f525374fb version: perform additional revision release
42e62aed5 target: Fix AndroidTarget pickling
f5cfcafb0 shutils: Remove shebang
7853d2c85 target: Run shutils.in in busybox
REVERT: 7866086ec shutils: Remove shebang
REVERT: 734b24987 target: Run shutils.in in busybox
REVERT: 23f663d14 target: Fix AndroidTarget pickling
REVERT: 235422855 devlib: Use async Target API
REVERT: be593120a target: Expose Target(max_async=50) parameter
REVERT: bec2c02fd target: Enable async methods
REVERT: fba315e76 utils/async: Add new utils.async module
REVERT: 981b69ff9 setup.py: Require Python >= 3.7
REVERT: 49e452046 setup.py: cleanup dependencies in setup.py
REVERT: d0b5c1a2a target: Make __getstate__ more future-proof
REVERT: dcfc28e3f target: Fix Target.get_connection()'s busybox
REVERT: 16c3f0e98 utils.misc: Make nullcontext work with asyncio

git-subtree-dir: external/devlib
git-subtree-split: 1196e336a5c014f843a496be70f41b0e6015c80f