Merge pull request #19670 from vngrs/misspell_of_exist

correct spell of exist [ci skip]

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -568,7 +568,7 @@ def rename_table(table_name, new_name)
       #   Set to +:cascade+ to drop dependent objects as well.
       #   Defaults to false.
       # [<tt>:if_exists</tt>]
-      #   Set to +true+ to make drop table command fail safe when table does not exists.
+      #   Set to +true+ to only drop the table if it exists.
       #   Defaults to false.
       # [<tt>:temporary</tt>]
       #   Set to +true+ to drop temporary table.

activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb

@@ -93,7 +93,7 @@ def table_exists?(name)
         #   Set to +:cascade+ to drop dependent objects as well.
         #   Defaults to false.
         # [<tt>:if_exists</tt>]
-        #   Set to +true+ to make drop table command fail safe when table does not exists.
+        #   Set to +true+ to only drop the table if it exists.
         #   Defaults to false.
         def drop_table(table_name, options = {})
           execute "DROP TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}#{' CASCADE' if options[:force] == :cascade}"