.pytool/SpellCheck: Fix silent cspell run error

[Javagedes]

Description

In the implementation of the SpellCheck prior to this commit, the logic
assumed that if it was able to successfully call cspell --version to
get the version, then any future usage of cspell would work without
error. PR #11783 brought to light an issue in this logic where if the
node version was too out of date, cspell could successfully run
cspell --version but would hit a runtime error when actually
performing a spell check on a package. This ultimetly resulted in
cspell not running for any package but still reporting a "Success".

This commit updates the error handling logic in the SpellCheck when
running cspell to ensure that when cspell error lines were reported, at
least one misspelled word must be found. In the scenario where error
lines are reported, but no misspelled words were found, we now assume a
runtime error occurred in cspell, log it, and fail the plugin.

• Breaking change?
  • Breaking change - Does this PR cause a break in build or boot behavior?
  • Examples: Does it add a new library class or move a module to a different repo.
• Impacts security?
  • Security - Does this PR have a direct security impact?
  • Examples: Crypto algorithm change or buffer overflow fix.
• Includes tests?
  • Tests - Does this PR include any explicit test code?
  • Examples: Unit tests or integration tests.

How This Was Tested

Continious Integration

Integration Instructions

N/A