Add new localizable strings for sign tooltips

re: OpenRCT2/OpenRCT2#8593

These strings use high IDs right now and are probably
not entirely suited for direct inclusion. There is also
some duplication in that "No entry" had to be unique,
as the actual no entry string is "No entry - -".

data/language/en-GB.txt

@@ -3755,6 +3755,8 @@ STR_6304    :Open scenery picker
 STR_6305    :Multithreading
 STR_6306    :{SMALLFONT}{BLACK}Experimental option to use multiple threads to render, may cause instability.
 STR_6307    :Colour scheme: {BLACK}{STRINGID}
+STR_6308    :“{STRINGID}{OUTLINE}{TOPAZ}”{NEWLINE}{STRINGID}
+STR_6309    :{RED}No entry
 
 #############
 # Scenarios #

src/openrct2/localisation/StringIds.h

@@ -3939,6 +3939,9 @@ enum
 
     STR_TILE_INSPECTOR_COLOUR_SCHEME = 6307,
 
+    STR_MAP_TOOLTIP_BANNER_STRINGID_STRINGID = 6308,
+    STR_NO_ENTRY_TOOLTIP = 6309,
+
     // Have to include resource strings (from scenarios and objects) for the time being now that language is partially working
     STR_COUNT = 32768
 };