typo fix (#832)

Resolves #828

Author: mattwojo

TerminalDocs/tutorials/shell-integration.md

@@ -194,7 +194,7 @@ function prompt {
 
 ### Command Prompt
 
-Command Prompt sources it's prompt from the `PROMPT` environment variable. CMD.exe reads `$e` as the `ESC` character.  Unfortunately, CMD.exe doesn't have a way to get the return code of the previous command in the prompt, so we're not able to provide success / error information in CMD prompts.
+Command Prompt sources its prompt from the `PROMPT` environment variable. CMD.exe reads `$e` as the `ESC` character.  Unfortunately, CMD.exe doesn't have a way to get the return code of the previous command in the prompt, so we're not able to provide success / error information in CMD prompts.
 
 You can change the prompt for the current CMD.exe instance by running: