Added InstanceDir to SQL composite

[rchristman89]

Pull Request (PR) description

This Pull Request (PR) fixes the following issues

Task list

• [ ] Added an entry to the change log under the Unreleased section of the file CHANGELOG.md. Entry should say what was changed and how that affects users (if applicable), and reference the issue being resolved (if applicable).
• [ ] Resource documentation added/updated in README.md.
• [ ] Resource parameter descriptions added/updated in README.md, schema.mof and comment-based help.
• [ ] Comment-based help added/updated.
• [ ] Localization strings added/updated in all localization files as appropriate.
• [ ] Examples appropriately added/updated.
• [ ] Unit tests added/updated. See DSC Community Testing Guidelines.
• [ ] Integration tests added/updated (where possible). See DSC Community Testing Guidelines.
• [ ] New/changed code adheres to DSC Community Style Guidelines.

---

This change is 

[codecov[bot]]

Codecov Report

Merging #60 into master will not change coverage. The diff coverage is n/a.

@@          Coverage Diff          @@
##           master    #60   +/-   ##
=====================================
  Coverage      97%    97%           
=====================================
  Files          33     33           
  Lines        3552   3552           
=====================================
  Hits         3464   3464           
  Misses         88     88