Use Ruby ==2.5.2== 2.5.3 (#9003)

* Use Ruby 2.5.2

* Specify 2.5.2p104 as RUBY VERSION

Heorku refers to RUBY VERSION in Gemfile.lock

* Use ruby-2.5.3

.ruby-version

@@ -1 +1 @@
-2.5.1
+2.5.3

Gemfile.lock

@@ -763,7 +763,7 @@ DEPENDENCIES
   webpush
 
 RUBY VERSION
-   ruby 2.5.0p0
+   ruby 2.5.3p105
 
 BUNDLED WITH
    1.16.5