misc/kate: fix multiline raw string syntax highlighting error.

From VisualFC.
Fixes #4862.

R=golang-dev, minux.ma, r
CC=golang-dev
https://golang.org/cl/7568043

misc/kate/go.xml

@@ -95,7 +95,7 @@
         <HlCHex attribute="Hex" context="#stay"/>
         <HlCChar attribute="Char" context="#stay"/>
         <DetectChar attribute="String" context="String" char="&quot;"/>
-        <DetectChar attribute="Multiline String" context="Multiline String" char="`"/>
+        <DetectChar attribute="String" context="Multiline String" char="`"/>
         <Detect2Chars attribute="Comment" context="Comment 1" char="/" char1="/"/>
         <Detect2Chars attribute="Comment" context="Comment 2" char="/" char1="*" beginRegion="Comment"/>
         <AnyChar attribute="Symbol" context="#stay" String=":!%&amp;()+,-/.*&lt;=&gt;?[]|~^&#59;"/>