Updated the escape_double_quotes() function such that the function now escapes both double quotes and backslashes in the input string.
Changes Made:
- Renamed the function to escape_quotes_and_backslashes
- Modified the condition in the first loop to increment the value of 'escaped_length' for both double quotes and backslashes.
- Modified the condition in second loop to add a backslash before the current character if it is a double quote or a backslash.
Resolves: #769