Show version of nodes in output of TAP tests

Show version of nodes in output of TAP tests

This commit adds the version information of a node initialized by
Cluster.pm, that may vary depending on the install_path given by the
test.  The code was written so as the node information, that includes
the version number, was dumped before the version number was set.

This is particularly useful for the pg_upgrade TAP tests, that may mix
several versions for cross-version runs.  The TAP infrastructure also
allows mixing nodes with different versions, so this information can be
useful for out-of-core tests.

Backpatch down to v15, where Cluster.pm and the pg_upgrade TAP tests
have been introduced.

Author: Potapov Alexander <[email protected]>
Reviewed-by: Daniel Gustafsson <[email protected]>
Discussion: https://postgr.es/m/e59bb-692c0a80-5-6f987180@170377126
Backpatch-through: 15