Pin mypy to 0.790 to prevent linting errors when running v 0.8

[jdavcs]

Running make update-dependencies will update mypy to version 0.8, which will cause the following error:

mypy run-test: commands[0] | mypy test lib
lib/galaxy/tools/bundled/data_source/data_source.py: error: Duplicate module named 'data_source' (also at 'test/functional/tools/data_source.py')
lib/galaxy/tools/bundled/data_source/data_source.py: error: Are you missing an __init__.py?
Found 2 errors in 1 file (errors prevented further checking)
ERROR: InvocationError for command /home/runner/work/galaxy/galaxy/.tox/mypy/bin/mypy test lib (exited with code 2)

I'm looking into the error, but for now I think it's reasonable to just pin it.

[jdavcs]

It appears that mypy 0.790 was not discovering all modules to test, which was a bug, fixed in 0.8 (see python/mypy#8548 and python/mypy#9614). In our case, running mypy separately on test and then on lib solves the error cited above (duplicate module names), but then it discovers more modules (1648 vs 1504) - and more errors (see below). The most recent version (0.812) provides a way to exclude directories, but given the variety of errors it finds, I don't think it's a viable solution.
I haven't looked closely at the newly discovered errors, but in any case it seems reasonable to stick with 0.790 until we address all these errors.

(.venv) rivendell$ mypy test lib
lib/galaxy/tools/bundled/data_source/data_source.py: error: Duplicate module named 'data_source' (also at 'test/functional/tools/data_source.py')
lib/galaxy/tools/bundled/data_source/data_source.py: note: Are you missing an __init__.py? Alternatively, consider using --exclude to avoid checking one of them.
Found 1 error in 1 file (errors prevented further checking)
(.venv) rivendell$ mypy test
test/integration/test_job_environments.py:19: error: First argument to namedtuple() should be 'JobEnviromentProperties', not 'JobEnvironmentProperties'
test/unit/tools/test_toolbox.py:38: error: First argument to namedtuple() should be 'REPO_TYPE', not 'DEFAULT_TEST_REPO'
test/integration/test_cli_runners.py:15: error: First argument to namedtuple() should be 'RemoteConnection', not 'remote_connection'
test/integration/test_kubernetes_runner.py:25: error: First argument to namedtuple() should be 'Config', not 'ConfigTuple'
test/integration/test_datatype_upload.py:18: error: First argument to namedtuple() should be 'TestData', not 'UploadDatatypesData'
test/integration/test_repository_operations.py:9: error: First argument to namedtuple() should be 'REPO_TYPE', not 'Repository'
Found 6 errors in 6 files (checked 292 source files)
(.venv) rivendell$ mypy lib
lib/galaxy/tools/bundled/metag_tools/blat_wrapper.py:7: error: Unsupported operand types for >= ("_version_info" and "float")
lib/galaxy/tools/bundled/filters/sff_extract.py:45: error: Need type annotation for 'ssahapematches' (hint: "ssahapematches: Dict[<type>, <type>] = ...")
lib/galaxy/tools/bundled/filters/sff_extract.py:47: error: Need type annotation for 'linkerlengths' (hint: "linkerlengths: Dict[<type>, <type>] = ...")
lib/galaxy/tools/bundled/metag_tools/shrimp_color_wrapper.py:12: error: Unsupported operand types for >= ("_version_info" and "float")
lib/galaxy/tools/bundled/extract/liftOver_wrapper.py:60: error: Incompatible types in assignment (expression has type "float", variable has type "str")
lib/galaxy/tools/bundled/extract/liftOver_wrapper.py:76: error: Item "None" of "Optional[IO[bytes]]" has no attribute "read"
lib/galaxy/tools/bundled/next_gen_conversion/solid2fastq.py:11: error: Module 'string' has no attribute 'maketrans'
lib/galaxy/tools/bundled/next_gen_conversion/solid2fastq.py:11: error: Name 'maketrans' already defined on line 9
lib/galaxy/tool_util/deps/mulled/util.py:19: error: First argument to namedtuple() should be 'PARSED_TAG', not 'ParsedTag'
lib/galaxy/tool_shed/tool_shed_registry.py:16: error: First argument to namedtuple() should be 'AUTH_TUPLE', not 'AuthSetting'
lib/galaxy/tool_util/deps/mulled/mulled_build_files.py:29: error: First argument to namedtuple() should be 'FALLBACK_LINE_TUPLE', not '_Line'
lib/galaxy/tools/toolbox/base.py:58: error: First argument to namedtuple() should be '_ToolConfRepository', not 'ToolConfRepository'
lib/galaxy/tools/__init__.py:194: error: First argument to namedtuple() should be 'safe_update', not 'SafeUpdate'
Found 13 errors in 10 files (checked 1356 source files)

[jdavcs]

Failing tests unrelated.

[jmchilton]

I merged two related PR that created conflicting fixture data huh? Opps.

[github-actions]

This PR was merged without a "kind/" label, please correct.