pyproject: use labgrid pyserial fork

Newer pypi releases forbid dependencies that are not also hosted on
pypi. To this end I have upgraded out pyserial fork with pyproject.toml
support and a test, build and release pipeline. We can switch over to a
pypi provided pyserial-labgrid now.

Signed-off-by: Rouven Czerwinski <r.czerwinski@pengutronix.de>
(cherry picked from commit 7bd2a6b)

Author: Emantor

pyproject.toml

@@ -35,7 +35,7 @@ dependencies = [
     "jinja2==3.0.2",
     "packaging==21.0",
     "pexpect==4.8.0",
-    "pyserial @ git+https://github.com/labgrid-project/pyserial.git@v3.4.0.1",
+    "pyserial-labgrid>=3.4.0.1",
     "pytest==7.2.2",
     "pyudev==0.22.0",
     "pyusb==1.2.1",