Remove : from country code rule

Signed-off-by: ClemensLinnhoff <[email protected]>

Author: ClemensLinnhoff

osi_groundtruth.proto

@@ -127,7 +127,7 @@ message GroundTruth
     // [1] ISO International Organization for Standardization. (2013). <em>ISO 3166-1 Codes for the representation of names of countries and their subdivisions - Part 1: Country codes</em>. (ISO 3166-1:2013). Geneva, Switzerland.
     //
     // \rules
-    // is_iso_country_code:
+    // is_iso_country_code
     // \endrules
     //
     optional uint32 country_code = 13;