Added Auto-prepend https:// to URLs without scheme in termux-open-url

[noob6t5]

In this PR I have added script for the https:// scheme to URLs that do not already include a scheme.I have specifically added support for https:// as it is more secure compared to http://. Since security is a priority, I chose to default to https:// to ensure that URLs are opened over a secure connection whenever possible. http:// support has not been added for this reason. We can add later too.

Before the Change: If a user tried to open a URL like google.com without specifying the scheme, the script would fail, and the user would not be able to visit the link.

After the Change: Now, if a user provides a URL without a scheme (e.g., google.com), the script automatically adds https:// to the URL, redirecting user from a browser.