reason typo

Signed-off-by: Gabrielė Stravinskaitė <gabriele.stravinskaite@vinted.com>

Author: GStrawinsky

sig/open_feature/sdk/provider/reason.rbs

@@ -8,7 +8,7 @@ module OpenFeature
         SPLIT: String
         CACHED: String
         DISABLED: String
-        TARGETING_MATCH_SPLIT: string
+        TARGETING_MATCH_SPLIT: String
         UNKNOWN: String
         STALE: String
         ERROR: String