Python: Allow function calling stepwise planner to use AzureOpenAI chat service

[moonbox3]

Motivation and Context

The first iteration of the function calling stepwise planner only used OpenAI. Now allow AzureChatService to use the planner.

Description

This PR:

• Allows the use of AzureOpenAI for the FC Stepwise Planner
• Fixes some formatting issues when generating the names/metadata of Plugins. .NET gets the function metadata as JSON, and the Azure Model performs much better with it formatted like this.
• Fix some missing spaces in the constant message used in the planner -- Azure is treating the new lines in that const message incorrectly and it causes content filtering results (reaching out to the team to understand why this is).

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the SK Contribution Guidelines and the pre-submission formatting script raises no violations
• All unit tests pass, and I have added new tests where possible
• I didn't break anyone 😄

[markwallace-microsoft]

Python 3.8 Test Coverage Report •

File	Stmts	Miss	Cover	Missing
semantic_kernel/core_plugins
time_plugin.py	84	6	93%	61, 71–72, 181–182, 231
semantic_kernel/planners/function_calling_stepwise_planner
function_calling_stepwise_planner.py	94	36	62%	113–171, 202–207
TOTAL	5370	1020	81%

Python 3.8 Unit Test Overview

Tests	Skipped	Failures	Errors	Time
1190	11 💤	0 ❌	0 🔥	20.948s ⏱️

[juliomenendez]

Looks good, just one small extra import that I think is not needed