Raise more descriptive exceptions when wrapped JSON typing classes needs to be instantiated

Summary

Some JSON typing helper classes need to be instantiated so they can be converted to a JSON type dictionary. For example, th.Property("parameters_schema", th.ArrayType).to_dict() will produce an error while th.Property("parameters_schema", th.ArrayType(th.StringType)).to_dict() will not but the exception raised is not very descriptive of the underlying error.

Slack: https://meltano.slack.com/archives/C01PKLU5D1R/p1649694338239079

Steps to reproduce

import singer_sdk.typing as th

th.Property("parameters_schema", th.ArrayType).to_dict()

What is the current bug behavior?

An error is raised downstream when the type_dict is tried to be iterated assuming it's a dictionary, looking for specific keys, so the root cause gets lost.

What is the expected correct behavior?

A descriptive exception is raised. Something like

>>> import singer_sdk.typing as th
>>> th.Property("parameters_schema", th.ArrayType).to_dict()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/edgarramirez/Code/sdk/singer_sdk/typing.py", line 361, in to_dict
    type_dict = self.type_dict
  File "/Users/edgarramirez/Code/sdk/singer_sdk/typing.py", line 347, in type_dict
    raise ValueError(
ValueError: Type dict for <class 'singer_sdk.typing.ArrayType'> is not defined. Try instantiating it with a nested type such as ArrayType(StringType).
>>>

Relevant logs and/or screenshots

tap_workato/tests/test_core.py:7: in <module>
    from tap_workato.tap import TapWorkato
tap_workato/tap.py:8: in <module>
    from tap_workato.streams import (
tap_workato/streams.py:82: in <module>
    class RecipesStream(WorkatoStream):
tap_workato/streams.py:116: in RecipesStream
    th.ArrayType
../../../Library/Caches/pypoetry/virtualenvs/tap-workato-T66zip44-py3.7/lib/python3.7/site-packages/singer_sdk/typing.py:94: in to_dict
    return cast(dict, self.type_dict)
../../../Library/Caches/pypoetry/virtualenvs/tap-workato-T66zip44-py3.7/lib/python3.7/site-packages/singer_sdk/typing.py:374: in type_dict
    merged_props.update(w.to_dict())
../../../Library/Caches/pypoetry/virtualenvs/tap-workato-T66zip44-py3.7/lib/python3.7/site-packages/singer_sdk/typing.py:338: in to_dict
    type_dict = append_type(type_dict, "null")
../../../Library/Caches/pypoetry/virtualenvs/tap-workato-T66zip44-py3.7/lib/python3.7/site-packages/singer_sdk/helpers/_typing.py:38: in append_type
    if "anyOf" in result:
E   TypeError: argument of type 'property' is not iterable

Possible fixes

Add a check in Property.type_dict to see if the wrapped object actually has a type_dict of dict type.