* remove an unneeded ruff warning disable
* remove coding: utf-8 from Python code; PEP 3120 makes UTF-8 the
default encoding
* remove unusable shebang lines from Python code
* remove empty print strings
* disable warnings when file objects are stored; these instances can't
be handled with context managers
* use more consistent whitespace in Python code, fixing flake8 warnings
* set the executable bit on scorecard.py, making it easier to run
These fix ruff rules EXE001, FURB105, UP009, SIM115.
Also:
- drop two unreachable return statements.
- test_17_ssl_use: avoid implicit string concatenations in lists.
Reported by GitHub CodeQL
Closes#21916
With either /usr/sbin/sshd found or configured via --with-test-sshd=path
add tests for SCP down- and uploads, insecure, with known hosts or not,
with authorized user key or unauthorized one.
Working now with libssh and libssh2, using a hashed known_hosts file.
Closes#19934