Add the get_user_agent() method

Author: mdmintz

help_docs/method_summary.md

@@ -43,6 +43,8 @@ self.get_page_source()
 self.get_title()
 # Duplicates: self.get_page_title()
 
+self.get_user_agent()
+
 self.go_back()
 
 self.go_forward()

seleniumbase/fixtures/base_case.py

@@ -423,6 +423,10 @@ def get_title(self):
         """ The shorter version of self.get_page_title() """
         return self.get_page_title()
 
+    def get_user_agent(self):
+        user_agent = self.driver.execute_script("return navigator.userAgent;")
+        return user_agent
+
     def go_back(self):
         self.__last_page_load_url = None
         self.driver.back()