fix(Core/Spells): Spell ID Shadow Ward (Warlock) (#1971)

- Set correct ID of warlock spell Shadow Ward. It was set to -7235(Shadow Protection) which is wrong
- Correct spellID is 6229 (Shadow Ward)

data/sql/updates/pending_db_world/rev_1560493947655900000.sql

@@ -0,0 +1,3 @@
+INSERT INTO `version_db_world` (`sql_rev`) VALUES ('1560493947655900000');
+
+UPDATE `spell_script_names` SET `spell_id`=-6229 WHERE `ScriptName`='spell_warl_shadow_ward';

src/server/scripts/Spells/spell_warlock.cpp

@@ -1310,7 +1310,7 @@ class spell_warl_health_funnel : public SpellScriptLoader
         }
 };
 
-// -7235 - Shadow Ward
+// -6229 - Shadow Ward
 class spell_warl_shadow_ward : public SpellScriptLoader
 {
     public: