mrhlpr.json: don't allow parenthesis in commit description (MR 5840)

Outside of the (MR \d+) match, there should be no reason to have
parenthesis in the commit description

.mrhlpr.json

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