[ci] Use ruby-2.5.8

Author: jim80net

.github/workflows/rspec.yml

@@ -12,10 +12,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - name: Set up Ruby 2.5
+    - name: Set up Ruby 2.5.8
       uses: actions/setup-ruby@v1
       with:
-        ruby-version: 2.5.x
+        ruby-version: 2.5.8
     - name: Test with Rspec
       run: |
           gem install bundler

.ruby-version

@@ -1 +1 @@
-ruby-2.5.0
+ruby-2.5.8

Gemfile

@@ -1,4 +1,5 @@
 source 'https://rubygems.org'
+ruby '2.5.8'
 
 gem 'redis'
 gem 'dogapi'

Gemfile.lock

@@ -66,5 +66,8 @@ DEPENDENCIES
   rspec
   timecop
 
+RUBY VERSION
+   ruby 2.5.8p224
+
 BUNDLED WITH
-   1.17.3
+   2.1.4