SFTP Provider: Fix default folder permissions

[MatthieuBlais]

Relates #26226

Fixing default mode when creating a directory with paramiko and convert decimal mode to octal mode (paramiko documention)

• Updating test cases to confirm permissions after masking out the default umask are as we expect whenever we create a new folder.

[boring-cyborg]

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[uranusjr]

I don’t think this is a good fix. Instead we should change the default to 0o777.

[MatthieuBlais]

@uranusjr I can change the default value to 511 which is 0o777 instead. My only concern is that this function mkdir in this class uses decimal value as well. I think it can be confusing if they don't follow the same approach. Is it better to update this function as well?

def mkdir(self, path: str, mode: int = 777) -> None:
        """
        Creates a directory on the remote system.
        :param path: full path to the remote directory to create
        :param mode: permissions to set the directory with
        """
        conn = self.get_conn()
        conn.mkdir(path, mode=int(str(mode), 8))

[uranusjr]

Change them both to use octal. Using decimal is a bug in the first place. (We can keep the str case to allow "755" so ease transition.) We can do this in a provider (and bump the major version).

[potiuk]

cool !