Solving lint rule issues

The current source code of Autosubmit has many underlying issues that can be easily detected by linters.

Just running Ruff, we have the following rules that are violated:

$ ruff check --statistics autosubmit
191     F841    [*] unused-variable
 50     F401    [*] unused-import
 39     E721    [ ] type-comparison
 37     E402    [ ] module-import-not-at-top-of-file
 31     E722    [ ] bare-except
 18     F523    [ ] string-dot-format-extra-positional-arguments
 15     F541    [*] f-string-missing-placeholders
 15     F811    [ ] redefined-while-unused
 12     F901    [*] raise-not-implemented
  9     F821    [ ] undefined-name
  2     E712    [*] true-false-comparison
  2     F402    [ ] import-shadowed-by-loop-var
  1     E713    [*] not-in-test
  1     E731    [*] lambda-assignment

It will be nice to solve them to prevent future bugs and keep tracking them in future releases as part of our development process.

@bdepaula @dbeltran @egarriga