Clarify the scope of error highlighting in the SARIF report

[mmvpm]

Description

The SARIF viewer will highlight the portion of the file specified by physicalLocation.region to display the error.

Now we specify only region.startLine field, so the whole line will be highlighted:

But there is no need to highlight an empty space at the beginning of the line.

Expected behavior

An empty space at the beginning of the line is not highlighted: