Build against Alchemy main branch

Alchemy switched from master to main

Author: tvdeyen

.travis.yml

@@ -13,9 +13,9 @@ env:
     - ALCHEMY_BRANCH=4.5-stable
     - ALCHEMY_BRANCH=4.6-stable
     - ALCHEMY_BRANCH=5.0-stable
-    - ALCHEMY_BRANCH=master
+    - ALCHEMY_BRANCH=main
 matrix:
   fast_finish: true
   allow_failures:
-    - env: ALCHEMY_BRANCH=master
+    - env: ALCHEMY_BRANCH=main
 script: bundle exec rake

Gemfile

@@ -1,6 +1,6 @@
 source "https://rubygems.org"
 
-alchemy_branch = ENV.fetch("ALCHEMY_BRANCH", "master")
+alchemy_branch = ENV.fetch("ALCHEMY_BRANCH", "main")
 gem "alchemy_cms", github: "AlchemyCMS/alchemy_cms", branch: alchemy_branch
 
 # Specify your gem's dependencies in alchemy-solidus.gemspec