removes obsolete Node v14 from CI testing

[DougReeder]

The tests pass under Node 18 and 20 on MacOS 13, but under Node 18 on Debian, there is one failure, so adding Node 18 and 20 to CI will have to wait for a future PR.

test.issue3179.js-local-http
✓ #3179 conflicts synced, non-live replication (178ms)
1) #3179 conflicts synced, non-live sync

924 passing (46s)
17 pending
1 failing

1. test.issue3179.js-local-http Removing conflicting revision doesn't sync from local to remote #3179 conflicts synced, non-live sync:
   TypeError: Cannot read properties of undefined (reading '0')
   at tests/integration/test.issue3179.js:85:54
   at process.processTicksAndRejections (node:internal/process/task_queues:95:5)

[lucidNTR]

i see no downside to removing this, we should try to add an node 18 target too, are you sure this is reproducibly failing not just part of the flakyness? (see #8692)

[SourceR85]

I expect, Node 18 should work fine.
In #8664, I've tinkered a little bit with the future, node 20 seems to be a little bit more problematic.

[DougReeder]

If the tests are just flaky under Node 18 Debian, it's probably best to investigate before adding 18 to the CI. IMNSHO, tests failing in CI should mean something.

[SourceR85]

@DougReeder the test-suite is flaky in every node version...
I don't expect some wonder, by just updating to another version 😉

[alxndrsn]

Sadly this change breaks tests in new ways, e.g.

pouchdb-server (firefox, TYPE=find PLUGINS=pouchdb-find ADAPTERS=http npm test)

  1) test.ltgt.js $gt on nested field:

      expected 100 to equal 101
      + expected - actual

      -100
      +101

I think these should be addressed before merging.