{Core} Use from collections.abc import Iterable to support Python 3.10

[ermirh]

importing the ABCs from 'collections' instead of from 'collections.abc'
is deprecated since Python 3.3, and in 3.10 it will stop working.

Description
On Python 3.10 running any az commands show the following error:

$ az account list
The command failed with an unexpected error. Here is the traceback:
module 'collections' has no attribute 'Iterable'
Traceback (most recent call last):
  File "/usr/local/lib/python3.10/site-packages/knack/cli.py", line 231, in invoke
    cmd_result = self.invocation.execute(args)
  File "/usr/local/lib/python3.10/site-packages/azure/cli/core/commands/__init__.py", line 657, in execute
    raise ex
  File "/usr/local/lib/python3.10/site-packages/azure/cli/core/commands/__init__.py", line 720, in _run_jobs_serially
    results.append(self._run_job(expanded_arg, cmd_copy))
  File "/usr/local/lib/python3.10/site-packages/azure/cli/core/commands/__init__.py", line 703, in _run_job
    elif _is_paged(result):
  File "/usr/local/lib/python3.10/site-packages/azure/cli/core/commands/__init__.py", line 1119, in _is_paged
    if isinstance(obj, collections.Iterable) \
AttributeError: module 'collections' has no attribute 'Iterable'
To open an issue, please run: 'az feedback'

Testing Guide
Testing any az commands like: az account list or az account get-access-token

---

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[ghost]

Thank you for your contribution ermirh! We will review the pull request and get back to you soon.

[yonzhan]

@jiasli for awareness

[jiasli]

According to https://docs.python.org/3/library/collections.html

Deprecated since version 3.3, will be removed in version 3.10: Moved Collections Abstract Base Classes to the collections.abc module. For backwards compatibility, they continue to be visible in this module through Python 3.9.

> C:\Users\xxx\AppData\Local\Programs\Python\Python39\python.exe -V
Python 3.9.5
> C:\Users\xxx\AppData\Local\Programs\Python\Python39\python.exe -c "from collections import Iterable"
<string>:1: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated since Python 3.3, and in 3.10 it will stop working

So it still works in Python 3.9, but stops working in Python 3.10.