E002 prepare restructure (#440)

* (E001) update tests (v4.x.x)

[test_*] reorder imports

[tests_ModelicaDoE*] fix pylint hint

* use .items()

[tests_*] use OMSessionABC.get_version()

[test_ModelicaSystemCmd] use get_model_name() instead of access to private variable _model_name

[test_ModelicaSystemOMC] read file using utf-8 encoding / linter fix

[test_ModelicaSystemRunner] update test case

* ModelicaSystemRunner & OMCPath
* ModelicaSystemRunner & OMPathRunnerLocal
* ModelicaSystemRunner & OMPathRunnerBash
* ModelicaSystemRunner & OMPathRunnerBash using docker
* ModelicaSystemRunner & OMPathRunnerBash using WSL (not tested!)

[test_OMCPath] update test case

* OMCPath & OMCSessionZMQ
* OMCPath & OMCSessionLocal
* OMCPath & OMCSessionDocker
* OMCPath & OMCSessionWSL (not tested!)
* OMPathLocal & OMCSessionRunner
* OMPathBash & OMCSessionRunner
* OMPathBash & OMCSessionRunner in docker
* OMPathBash & OMCSessionRunner in WSL (not tested!)

add workflow to run unittests in ./tests

[test_OMParser] use only the public interface => om_parser_basic()

[test_OMTypedParser] rename file / use om_parser_typed()

update tests - do NOT run test_FMIRegression.py

reason:
* it is only a test for OMC / not OMPython specific
* furthermore, it is run automatically via cron job (= FMITest)

[test_ModelExecutionCmd] rename from test_ModelicaSystemCmd

* (E002) prepare restructure

[ModelicaSystemCmd] add missing docstring

[OMCSession] spelling fixes

[OMCSessionCmd] add warning about depreciated class

[OMCSessionABC] remove duplicated code; see OMSessionABC

[OMSessionRunnerABC] define class

[OMCSessionZMQ] call super()__init__()

[OMCPath] fix forward dependency on OMCSessionLocal

[OMSessionException] rename from OMCSessionException

[__init__] fix imports

---------

Co-authored-by: Adeel Asghar <adeel.asghar@liu.se>

Author: syntron

OMPython/ModelicaSystem.py

@@ -25,7 +25,7 @@
     ModelExecutionData,
     ModelExecutionException,
 
-    OMCSessionException,
+    OMSessionException,
     OMCSessionLocal,
 
     OMPathABC,
@@ -1688,7 +1688,7 @@ def sendExpression(self, expr: str, parsed: bool = True) -> Any:
         """
         try:
             retval = self._session.sendExpression(expr=expr, parsed=parsed)
-        except OMCSessionException as ex:
+        except OMSessionException as ex:
             raise ModelicaSystemError(f"Error executing {repr(expr)}: {ex}") from ex
 
         logger.debug(f"Result of executing {repr(expr)}: {textwrap.shorten(repr(retval), width=100)}")
@@ -2829,7 +2829,9 @@ def _prepare_structure_parameters(
 
 
 class ModelicaSystemCmd(ModelExecutionCmd):
-    # TODO: docstring
+    """
+    Compatibility class; in the new version it is renamed as MOdelExecutionCmd.
+    """
 
     def __init__(
             self,