Don't use --include-git-root option with osv-scanner (#1018)

The documentation wasn't clear on this; it makes it scan .git/, which
seems unnecessary for us.

Author: mhucka

.github/workflows/osv-scanner.yaml

@@ -88,7 +88,6 @@ jobs:
           scan-args: |-
             --format=json
             --output=old-results.json
-            --include-git-root
             --recursive
             ./
 
@@ -106,7 +105,6 @@ jobs:
           scan-args: |-
             --format=json
             --output=new-results.json
-            --include-git-root
             --recursive
             ./