Allow ssh transport protocol for a git module spec

!bug

* **Allow ssh transport protocol** ([puppetlabs#3237](puppetlabs#3237))

  Fix regression introduced by commit [0a09069](puppetlabs@0a09069).
  Allow install module from git private repository with SSH transport URI (e.g ssh://git@mygitlabserver:12345/namespace/myprivatemod.git)

lib/bolt/module_installer/specs/git_spec.rb

@@ -45,7 +45,7 @@ def initialize(init_hash, config = {})
 
           unless valid_url?(@git)
             raise Bolt::ValidationError,
-                  "Invalid URI #{@git}. Valid URIs must begin with 'git@', 'http://', or 'https://'."
+                  "Invalid URI #{@git}. Valid URIs must begin with 'git@', 'http://', 'https://' or 'ssh://'."
           end
         end
 
@@ -140,7 +140,7 @@ def sha
           return true if url.start_with?('git@')
 
           uri = URI.parse(url)
-          uri.is_a?(URI::HTTP) && uri.host
+          (uri.is_a?(URI::HTTP) || uri.scheme == "ssh") && uri.host
         rescue URI::InvalidURIError
           false
         end

spec/unit/module_installer/specs/git_spec_spec.rb

@@ -61,6 +61,11 @@
         /Option 'resolve'.*must be a Boolean/
       )
     end
+
+    it 'allow ssh URI' do
+      init_hash['git'] = 'ssh://myuser@github.com:12345/puppetlabs/puppetlabs-yaml'
+      expect { spec }.not_to raise_error
+    end
   end
 
   context '#to_hash' do