fix to stop removing instances of the artifact name that occur within the FileContainerItem path (issue: azure-pipelines-tasks#16522)

[nmonizms]

Context

For an artifact with name dist, the FileContainerProvider will strip away subdirectories that contain the artifact name in the path

For example:
dist\myapp\config.json
dist\myapp\en-us
dist\myapp\en-us\dist
dist\myapp\en-us\dist\assets
dist\myapp\en-us\dist\assets\feedback\readme.txt

The result of the copy is that it removes the nested folder called dist and we end with a file structure like below. Notice the “assets" directory is now directly under en-us instead of nested in the dist directory:

myapp\config.json
myapp\en-us
myapp\en-us\assets
myapp\en-us\assets\feedback\readme.txt

Addresses the issue reported in:
Download pipeline artifact breaks folder structure when downloading pipeline artifact, reopened #12682
Download pipeline artifact breaks folder structure when downloading pipeline artifact

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Description

This code change corrects the behavior to only remove the starting directory name instead of replacing all instances of artifact name in the path.

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Risk Assessment (Low / Medium / High)

Low: targeted fix to correct artifact name removal

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Unit Tests Added or Updated (Yes / No)

No

Additional Testing Performed

No