GEODE-8778: Change conserve-sockets default value to false

[DonalEvans]

• Update certain tests to explicitly set conserve-sockets=true to allow
  them to pass with the new default
• Update docs to reflect new default

Authored-by: Donal Evans doevans@vmware.com

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[jake-at-work]

Why are the two tests modified in this PR setting the the value against the new default? If the default is false now it stands to reason that unless a tests is explicitly testing socket conservation that it should use the new default of false.

[DonalEvans]

Why are the two tests modified in this PR setting the the value against the new default? If the default is false now it stands to reason that unless a tests is explicitly testing socket conservation that it should use the new default of false.

Thanks for bringing this up, Jake. After looking closer at the first test, ClusterDistributionManagerDUnitTest, it doesn't need to explicitly set conserve-sockets to true, just add an additional ignored exception due to a slightly different code path resulting in (expected) logging about ack-severe-alert-threshold being exceeded. I've modified the test to reflect this.

The second test, CloseConnectionTest is explicitly testing the behaviour of shared connections, so it requires that conserve-sockets=true. I think it was just an oversight to not set the value and instead rely on the default.

[jake-at-work]

Reviewed for content and looks good. Would like to see a comment about the 1 test that is explicitly setting conserve sockets true. I have not review for correctness or test failures.

[davebarnes97]

+1 for all the doc changes (mods to .erb source files).