Remove Ahoy ensure_uuid logic and uuidtools dependency

Ahoy 2.0.0 [1] introduced automatic UUID generation for visit_token and
visitor_token. As a result, the custom ensure_uuid method is no longer
needed and can be safely removed from the initializer.

Since we aren't manually generating UUIDs anymore, we no longer need
the uuidtools dependency.

[1] https://github.com/ankane/ahoy/blob/v2.0.0/README.md#token-generation

Gemfile

@@ -58,7 +58,6 @@ gem "sprockets-rails", "~> 3.5.2", require: "sprockets/railtie"
 gem "turbolinks", "~> 5.2.1"
 gem "turnout", "~> 2.5.0"
 gem "uglifier", "~> 4.2.1"
-gem "uuidtools", "~> 2.2.0"
 gem "view_component", "~> 3.23.1"
 gem "whenever", "~> 1.0.0", require: false
 gem "wicked_pdf", "~> 2.8.2"

Gemfile.lock

@@ -703,7 +703,6 @@ GEM
       unicode-emoji (~> 4.0, >= 4.0.4)
     unicode-emoji (4.0.4)
     uri (1.0.3)
-    uuidtools (2.2.0)
     version_gem (1.1.8)
     view_component (3.23.1)
       activesupport (>= 5.2.0, < 8.1)
@@ -834,7 +833,6 @@ DEPENDENCIES
   turbolinks (~> 5.2.1)
   turnout (~> 2.5.0)
   uglifier (~> 4.2.1)
-  uuidtools (~> 2.2.0)
   view_component (~> 3.23.1)
   web-console (~> 4.2.1)
   whenever (~> 1.0.0)

config/initializers/ahoy.rb

@@ -8,17 +8,17 @@ class Ahoy::Store < Ahoy::DatabaseStore
   end
 
   def track_visit(data)
-    data[:id] = ensure_uuid(data.delete(:visit_token))
+    data[:id] = ahoy.visit_token
-    data[:visitor_id] = ensure_uuid(data.delete(:visitor_token))
+    data[:visitor_id] = ahoy.visitor_token
     super(data)
   end
 
   def visit
     unless defined?(@visit)
       if ahoy.send(:existing_visit_token) || ahoy.instance_variable_get(:@visit_token)
-        @visit = visit_model.where(id: ensure_uuid(ahoy.visit_token)).take if ahoy.visit_token
+        @visit = visit_model.where(id: ahoy.visit_token).take if ahoy.visit_token
       elsif !Ahoy.cookies? && ahoy.visitor_token
-        @visit = visit_model.where(visitor_id: ensure_uuid(ahoy.visitor_token))
+        @visit = visit_model.where(visitor_id: ahoy.visitor_token)
                             .where(started_at: Ahoy.visit_duration.ago..)
                             .order(started_at: :desc)
                             .first
@@ -34,12 +34,6 @@ class Ahoy::Store < Ahoy::DatabaseStore
     Visit
   end
 
-  def ensure_uuid(id)
-    UUIDTools::UUID.parse(id).to_s
-  rescue
-    UUIDTools::UUID.sha1_create(UUIDTools::UUID.parse(Ahoy::Tracker::UUID_NAMESPACE), id).to_s
-  end
-
   def exclude?
     false
   end