mrhlpr.json: force lower-case at the beginning of commit description (MR 5840)

This is how it's enforced in the COMMITSTYLE

.mrhlpr.json

 {
     "subject_format": {
         "pass": [
-            "^(([a-z]+\\/\\)?\\([a-z\\-0-9*{}]+),?)+: [A-Za-z\\/\\-0-9*{}\\.,_&:=' ]+( \\(MR \\d+\\)|)$",
+            "^(([a-z]+\\/\\)?\\([a-z\\-0-9*{}]+),?)+: [a-z][A-Za-z\\/\\-0-9*{}\\.,_&:=' ]+( \\(MR \\d+\\)|)$",
             "^CI: [a-z-0-9*{}\\(\\)\\.,_ ][A-Za-z\\/\\-0-9*{}\\.,_ ]+( \\(MR \\d+\\)|)$",
             "^mrhlpr.json: [a-z-0-9*{}\\(\\)\\.,_ ][A-Za-z\\/\\-0-9*{}\\.,_ ]+( \\(MR \\d+\\)|)$",
             "^pmaports.cfg: [a-z-0-9*{}\\(\\)\\.,_ ][A-Za-z\\/\\-0-9*{}\\.,_ ]+( \\(MR \\d+\\)|)$"