Downgrade danger to keep supporting Ruby 2.6.

Gemfile

@@ -1,9 +1,6 @@
 source("https://rubygems.org")
 
-# We want to test with the latest master branch
-gem "danger"
+gem "danger", "~> 8" # Fixed on 8.x because 9.x uses Octokit 5.x which doesn't support Ruby 2.6, which is needed to run verify_docs lane in fastlane's main repo.
 gem "fastlane", git: "https://github.com/fastlane/fastlane"
 gem "rubocop", "0.49.1"
-
-# Needed for testing sample code
-gem "xcov"
+gem "xcov" # Needed for testing sample code

Gemfile.lock

@@ -80,7 +80,7 @@ GEM
       highline (~> 2.0.0)
     cork (0.3.0)
       colored2 (~> 3.1)
-    danger (9.0.0)
+    danger (8.6.1)
       claide (~> 1.0)
       claide-plugins (>= 0.9.2)
       colored2 (~> 3.1)
@@ -91,7 +91,7 @@ GEM
       kramdown (~> 2.3)
       kramdown-parser-gfm (~> 1.0)
       no_proxy_fix
-      octokit (~> 5.0)
+      octokit (~> 4.7)
       terminal-table (>= 1, < 4)
     declarative (0.0.20)
     digest-crc (0.6.4)
@@ -194,7 +194,7 @@ GEM
     nap (1.1.0)
     naturally (2.2.1)
     no_proxy_fix (0.1.2)
-    octokit (5.6.1)
+    octokit (4.25.1)
       faraday (>= 1, < 3)
       sawyer (~> 0.9)
     open4 (1.3.4)
@@ -279,7 +279,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  danger
+  danger (~> 8)
   fastlane!
   rubocop (= 0.49.1)
   xcov