Generalize continuous check in chain trajectory

[jaclark5]

Fixes #3546

Changes made in this Pull Request:

• Added a fix this issue with a base.ReaderBase method.

Note that the overwritten method in the LAMMPS reader was a solution that was integrated into my personal working version with very ugly if statements. I think a solution like this will keep things clean.

PR Checklist

• Tests?
• Docs?
• CHANGELOG updated?
• Issue raised/referenced?

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (58bbc44) 93.60% compared to head (e21f45f) 93.60%.

❗ Current head e21f45f differs from pull request most recent head de0fdcb. Consider uploading reports for the commit de0fdcb to get more accurate results

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #3849   +/-   ##
========================================
  Coverage    93.60%   93.60%           
========================================
  Files          193      193           
  Lines        25146    25152    +6     
  Branches      4055     4055           
========================================
+ Hits         23538    23544    +6     
  Misses        1092     1092           
  Partials       516      516           

Impacted Files	Coverage Δ
package/MDAnalysis/coordinates/LAMMPS.py	95.06% <100.00%> (+0.03%)	⬆️
package/MDAnalysis/coordinates/base.py	94.60% <100.00%> (+0.01%)	⬆️
package/MDAnalysis/coordinates/chain.py	86.69% <100.00%> (ø)

... and 1 file with indirect coverage changes

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[github-actions]

Linter Bot Results:

Hi @jaclark5! Thanks for making this PR. We linted your code and found the following:

Some issues were found with the formatting of your code.

Code Location	Outcome
main package	⚠️ Possible failure
testsuite	⚠️ Possible failure

Please have a look at the darker-main-code and darker-test-code steps here for more details: https://github.com/MDAnalysis/mdanalysis/actions/runs/5281931368/jobs/9556168994

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Please note: The black linter is purely informational, you can safely ignore these outcomes if there are no flake8 failures!

[jaclark5]

@MDAnalysis/coredevs I'm curious to know your thoughts on this change