xSQLServerScript: Fixing PSSA errors

[ChrisLGardner]

Pull Request (PR) description
As raised in #728 there are various ScriptAnalyzer errors from the parameters being marked as Mandatory = $false, this resolves those errors.

This Pull Request (PR) fixes the following issues:
Fixes #728

Task list:

• Change details added to Unreleased section of CHANGELOG.md?
• Added/updated documentation, comment-based help and descriptions in .schema.mof files where appropriate?
• Examples appropriately updated?
• New/changed code adheres to Style Guidelines?
• Unit and (optional) Integration tests created/updated where possible?

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This change is 

[msftclas]

@ChrisLGardner,
Thanks for having already signed the Contribution License Agreement. Your agreement was validated by Microsoft. We will now review your pull request.
Thanks,
Microsoft Pull Request Bot

[codecov-io]

Codecov Report

Merging #764 into dev will not change coverage.
The diff coverage is n/a.

@@         Coverage Diff         @@
##            dev   #764   +/-   ##
===================================
  Coverage    97%    97%           
===================================
  Files        30     30           
  Lines      3250   3250           
===================================
  Hits       3165   3165           
  Misses       85     85

[johlju]

@ChrisLGardner Thanks for fixing this and the others! Please add this change to the CHANGELOG.md.

[ChrisLGardner]

Done.

[johlju]

Reviewed 1 of 1 files at r1, 1 of 1 files at r3.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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CHANGELOG.md, line 55 at r3 (raw file):

[Issue #728]

Please use lower-case 'i' in issue to be consequent with the other entries.

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Comments from Reviewable

[johlju]

Review status: all files reviewed at latest revision, 2 unresolved discussions.

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CHANGELOG.md, line 55 at r3 (raw file):

- -

Please remove on of the dashes here as well.

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Comments from Reviewable

[ChrisLGardner]

Review status: 1 of 2 files reviewed at latest revision, 2 unresolved discussions.

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CHANGELOG.md, line 55 at r3 (raw file):

Previously, johlju (Johan Ljunggren) wrote…

[Issue #728]

Please use lower-case 'i' in issue to be consequent with the other entries.

Done.

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CHANGELOG.md, line 55 at r3 (raw file):

Previously, johlju (Johan Ljunggren) wrote…

Please remove on of the dashes here as well.

Done.

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Comments from Reviewable

[johlju]

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Reviewed 1 of 1 files at r4.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable