Correct Env name in the UI to be tested

Author: ono-max

test/support/assertions.rb

@@ -3,7 +3,7 @@
 module DEBUGGER__
   module AssertionHelpers
     def assert_line_num(expected)
-      case ENV['RUBY_DEBUG_TEST_UI']
+      case get_target_ui
       when 'terminal'
         @scenario.push(Proc.new { |test_info|
           msg = "Expected line number to be #{expected.inspect}, but was #{test_info.internal_info['line']}\n"

test/support/protocol_test_case.rb

@@ -280,7 +280,7 @@ def assert_watch_result expected,  expression, frame_idx: 0
     # Not API
 
     def execute_dap_scenario scenario
-      ENV['RUBY_DEBUG_TESTED_UI'] = 'vscode'
+      ENV['RUBY_DEBUG_TEST_UI'] = 'vscode'
 
       @remote_info = setup_unix_domain_socket_remote_debuggee
       Timeout.timeout(TIMEOUT_SEC) do
@@ -305,7 +305,7 @@ def execute_dap_scenario scenario
     end
 
     def execute_cdp_scenario scenario
-      ENV['RUBY_DEBUG_TESTED_UI'] = 'chrome'
+      ENV['RUBY_DEBUG_TEST_UI'] = 'chrome'
 
       @remote_info = setup_tcpip_remote_debuggee
       Timeout.timeout(TIMEOUT_SEC) do
@@ -590,7 +590,7 @@ def find_response key, target, direction
     end
 
     def get_target_ui
-      ENV['RUBY_DEBUG_TESTED_UI']
+      ENV['RUBY_DEBUG_TEST_UI']
     end
 
     # FIXME: Commonalize this method.