[release/8.0] `PEImage` should not permit `m_path` field mutation (#91085)

[release/8.0] `PEImage` should not permit `m_path` field mutation (#91085)

* Remove cases where PEImage::m_path was mutated. Create m_pathHash field and remove function. Remove FEATURE_CASE_SENSITIVE_FILESYSTEM.

* Address contract violations

* Remove try/catch and replace with assert

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Co-authored-by: Aaron R Robinson <arobins@microsoft.com>