Yearly copyright update

[nwillhoft]

Description

Yearly copyright update to include the new year.

Use case

N/A

Benefits

N/A

Possible Drawbacks

N/A

Testing

Have you added/modified unit tests to test the changes?

N/A

If so, do the tests pass/fail?

N/A. Running greps on files confirms that all files have been updated accordingly:

$ cd Bio-DB-HTS
$ git checkout copyright-2021
$ git grep -l -P 'Copyright \[\d+-2021\]' | wc -l
      38
# as expected, there are no longer any files with a 2020 copyright end date
$ git grep -l -P 'Copyright \[\d+-2020\]' | wc -l
       0
# there are 2 extra files containing the word 'Copyright'
$ git grep -l -F 'Copyright' | wc -l
      40
# check that these 2 extra files did not need updating (see next steps)
# turns out these two extra files simply contain the string 'Copyright' and did not require updating
# here are my methods for clarity:
$ git grep -l -P 'Copyright \[\d+-2021\]' > 2021-file-list
$ git grep -l -F 'Copyright' > copyright-file-list
$ diff 2021-file-list copyright-file-list
1a2
> Changes
25a27
> ppport.h
$ grep 'Copyright' Changes
  * Copyright updates
$ grep 'Copyright' ppport.h
Version 3.x, Copyright (c) 2004-2009, Marcus Holland-Moritz.
Version 2.x, Copyright (C) 2001, Paul Marquess.
Version 1.x, Copyright (C) 1999, Kenneth Albanowski.

Have you run the entire test suite and no regression was detected?

The test build passes.