Fix `presicion` -> `precision`

This fix is necessary to test precision's default correctly.

activerecord/test/cases/ar_schema_test.rb

@@ -160,7 +160,7 @@ def test_timestamps_without_null_set_null_to_false_on_add_timestamps
   end
 
   if subsecond_precision_supported?
-    def test_timestamps_sets_presicion_on_create_table
+    def test_timestamps_sets_precision_on_create_table
       ActiveRecord::Schema.define do
         create_table :has_timestamps do |t|
           t.timestamps
@@ -171,7 +171,7 @@ def test_timestamps_sets_presicion_on_create_table
       assert @connection.column_exists?(:has_timestamps, :updated_at, precision: 6, null: false)
     end
 
-    def test_timestamps_sets_presicion_on_change_table
+    def test_timestamps_sets_precision_on_change_table
       ActiveRecord::Schema.define do
         create_table :has_timestamps
 
@@ -185,7 +185,7 @@ def test_timestamps_sets_presicion_on_change_table
     end
 
     if ActiveRecord::Base.connection.supports_bulk_alter?
-      def test_timestamps_sets_presicion_on_change_table_with_bulk
+      def test_timestamps_sets_precision_on_change_table_with_bulk
         ActiveRecord::Schema.define do
           create_table :has_timestamps
 
@@ -199,7 +199,7 @@ def test_timestamps_sets_presicion_on_change_table_with_bulk
       end
     end
 
-    def test_timestamps_sets_presicion_on_add_timestamps
+    def test_timestamps_sets_precision_on_add_timestamps
       ActiveRecord::Schema.define do
         create_table :has_timestamps
         add_timestamps :has_timestamps, default: Time.now

activerecord/test/cases/migration/compatibility_test.rb

@@ -242,9 +242,9 @@ def migrate(x)
       private
         def precision_implicit_default
           if current_adapter?(:Mysql2Adapter)
-            { presicion: 0 }
+            { precision: 0 }
           else
-            { presicion: nil }
+            { precision: nil }
           end
         end
     end