Update SPDX spec links to current

[bact]

Existing links are dead-links due to website structure changes.

For example, https://spdx.github.io/spdx-spec/introduction/ is a dead link.
That page is now at https://spdx.github.io/spdx-spec/v2.2.2/introduction/.

--

SPDX 2.2.2 is a patch version of 2.2.

There is no technical differences between 2.2, 2.2.1, and 2.2.2 (2.2.1 is a reformat and renumbering of chapters/annexes for ISO submission, 2.2.2 is a grammar/typo fix of 2.2.1, according to https://github.com/spdx/using/blob/main/docs/diffs-from-previous-editions.md#a4-differences-between-v221-and-v22- and https://spdx.github.io/spdx-spec/v2.2.2/diffs-from-previous-editions/ )

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.13%. Comparing base (84bbf4c) to head (fe375be).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #765   +/-   ##
=======================================
  Coverage   70.13%   70.13%           
=======================================
  Files         277      277           
  Lines        8651     8651           
  Branches     1006     1006           
=======================================
  Hits         6067     6067           
  Misses       2065     2065           
  Partials      519      519           

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