Remove float8-small-is-zero regression test variant.

Andrew Gierth <rhodiumtoad@postgresql.org>

Commit: 6ee89952d4e944b5c9c26181d418395b2f5d5fd8
Author: Andrew Gierth <rhodiumtoad@postgresql.org>
Date: 2019-02-16T22:11:04Z
Releases: 12.0
Remove float8-small-is-zero regression test variant.

Since this was also the variant used as an example in the docs, update
the docs to use float4-misrounded-input as an example instead, since
that is now the only remaining variant file.

Files

Documentation touched