Doc: fix confusion about LEAKPROOF in syntax summaries.

Tom Lane <tgl@sss.pgh.pa.us>

Commit: 5c22cf0e73397dfb83a91b14f10ca610dd83cff3
Author: Tom Lane <tgl@sss.pgh.pa.us>
Date: 2021-06-23T18:27:13Z
Releases: 11.13
Doc: fix confusion about LEAKPROOF in syntax summaries.

The syntax summaries for CREATE FUNCTION and allied commands
made it look like LEAKPROOF is an alternative to
IMMUTABLE/STABLE/VOLATILE, when of course it is an orthogonal
option.  Improve that.

Per gripe from aazamrafeeque0.  Thanks to David Johnston for
suggestions.

Discussion: https://postgr.es/m/162444349581.694.5818572718530259025@wrigleys.postgresql.org

Files

Documentation touched

Discussion