#05AB1E, 22 bytes

Assumes that the URL is passed without the https://.

###Code:

.w’®Ã-ƒ¢’¡`"<li>"¡2è#¬

Uses the 05AB1E encoding. Cannot be tried online, because of internet access.

###Explanation:

.w                       # Receive implicit input and read all data from the url
  ’®Ã-ƒ¢’¡               # Split on the string "header-details"
          `              # Flatten once which leaves the last element on top of the stack
           "<li>"¡       # Split on the string "<li>"
                  2è     # Get the third element
                    #    # Split on spaces
                     ¬   # Retrieve the first element 

This is what I get when running in the command line:

05AB1E, 22 bytes

Assumes that the URL is passed without the https://.

Code:

.w’®Ã-ƒ¢’¡`"<li>"¡2è#¬

Uses the 05AB1E encoding. Cannot be tried online, because of internet access.

Explanation:

.w                       # Receive implicit input and read all data from the url
  ’®Ã-ƒ¢’¡               # Split on the string "header-details"
          `              # Flatten once which leaves the last element on top of the stack
           "<li>"¡       # Split on the string "<li>"
                  2è     # Get the third element
                    #    # Split on spaces
                     ¬   # Retrieve the first element 

This is what I get when running in the command line:

#05AB1E, 22 bytes

Assumes that the URL is passed without the https://. Code:

.w’®Ã-ƒ¢’¡`"<li>"¡2è#¬

Uses the 05AB1E encoding. Cannot be tried online, because of internet access.

This is what I get when running in the command line:

#05AB1E, 22 bytes

Assumes that the URL is passed without the https://.

###Code:

.w’®Ã-ƒ¢’¡`"<li>"¡2è#¬

Uses the 05AB1E encoding. Cannot be tried online, because of internet access.

###Explanation:

.w                       # Receive implicit input and read all data from the url
  ’®Ã-ƒ¢’¡               # Split on the string "header-details"
          `              # Flatten once which leaves the last element on top of the stack
           "<li>"¡       # Split on the string "<li>"
                  2è     # Get the third element
                    #    # Split on spaces
                     ¬   # Retrieve the first element 

This is what I get when running in the command line:

#05AB1E, 22 bytes

Assumes that the URL is passed without the https://. Code:

.w’®Ã-ƒ¢’¡`"<li>"¡2è#¬

Uses the 05AB1E encoding. Cannot be tried online, because of internet access.

#05AB1E, 22 bytes

Assumes that the URL is passed without the https://. Code:

.w’®Ã-ƒ¢’¡`"<li>"¡2è#¬

Uses the 05AB1E encoding. Cannot be tried online, because of internet access.

This is what I get when running in the command line: