Add additional ERB DummyCompiler tests

This adds a few additional tests to the commits by eileencodes (https://github.com/rails/rails/pull/35497) and rafaelfranca (cfa22f1a4b). The additional tests cover several more ERB tag formatting cases such as multiline tags, conditional statements that result in duplicate keys, and multiple erb statements on a single line.

railties/test/application/rake/dbs_test.rb

@@ -68,6 +68,60 @@ module ApplicationTests
         db_create_and_drop("db/development.sqlite3", environment_loaded: false)
       end
 
+      test "db:create and db:drop don't raise errors when loading YAML with multiline ERB" do
+        app_file "config/database.yml", <<-YAML
+          development:
+            database: <%=
+              Rails.application.config.database
+            %>
+            adapter: sqlite3
+        YAML
+
+        app_file "config/environments/development.rb", <<-RUBY
+          Rails.application.configure do
+            config.database = "db/development.sqlite3"
+          end
+        RUBY
+
+        db_create_and_drop("db/development.sqlite3", environment_loaded: false)
+      end
+
+      test "db:create and db:drop don't raise errors when loading YAML containing conditional statements in ERB" do
+        app_file "config/database.yml", <<-YAML
+          development:
+          <% if  Rails.application.config.database %>
+            database: <%= Rails.application.config.database %>
+          <% else  %>
+            database: db/default.sqlite3
+          <% end  %>
+            adapter: sqlite3
+        YAML
+
+        app_file "config/environments/development.rb", <<-RUBY
+          Rails.application.configure do
+            config.database = "db/development.sqlite3"
+          end
+        RUBY
+
+        db_create_and_drop("db/development.sqlite3", environment_loaded: false)
+      end
+
+      test "db:create and db:drop don't raise errors when loading YAML containing multiple ERB statements on the same line" do
+        app_file "config/database.yml", <<-YAML
+          development:
+            database: <% if  Rails.application.config.database %><%= Rails.application.config.database %><% else  %>db/default.sqlite3<% end %>
+            adapter: sqlite3
+        YAML
+
+        app_file "config/environments/development.rb", <<-RUBY
+          Rails.application.configure do
+            config.database = "db/development.sqlite3"
+          end
+        RUBY
+
+        db_create_and_drop("db/development.sqlite3", environment_loaded: false)
+      end
+
       def with_database_existing
         Dir.chdir(app_path) do
           set_database_url