Add Pester Test to Check for Duplicate Function Definitions

[mdaneri]

Description:
This pull request introduces a new Pester test that verifies if any function in the Pode codebase has more than one definition. Duplicate function definitions can cause unexpected behavior and make maintenance difficult. This test aims to detect and prevent such issues.

Changes:
New Pester Test Script:
Created a new test script named DuplicateFunctionCheck.Tests.ps1 under the tests directory.
The script recursively scans all .ps1 and .psm1 files in the Pode module for function definitions.
Groups all function names and identifies any duplicate definitions based on the function names.
Reports the file path and line numbers for any duplicates found.
Purpose:
Adding this test helps maintain code quality and ensures that all function names are unique within the module. If a duplicate is found, the test fails and outputs the offending function names along with their respective file paths and line numbers for easy identification and resolution.

Example Output:
If duplicate function definitions are detected, the following message will be displayed:

The following functions have multiple definitions:
Function: MyDuplicateFunction
 - File: C:\path\to\file1.ps1, Line: 45
 - File: C:\path\to\file2.ps1, Line: 67

[Badgerati]

LGTM