pgsql: injection_points: Introduce runtime conditions

injection_points: Introduce runtime conditions

This adds a new SQL function injection_points_set_local() that can be
used to force injection points to be run only in the process where they
are attached. This is handy for SQL tests to:
- Detach automatically injection points when the process exits.
- Allow tests with injection points to run concurrently with other test
suites, so as such modules do not have to be marked with
NO_INSTALLCHECK.

Currently, the only condition that can be registered is for a PID.
This could be extended to more kinds later, if required, like database
names/OIDs, roles, or more concepts I did not consider.

Using a single function for SQL scripts is an idea from Heikki
Linnakangas.

Reviewed-by: Andrey Borodin
Discussion: https://postgr.es/m/ZfP7IDs9TvrKe49x@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f587338dec87d3c35b025e131c5977930ac69077

Modified Files
--------------
.../injection_points/expected/injection_points.out | 77 +++++++++
.../injection_points/injection_points--1.0.sql | 11 ++
.../modules/injection_points/injection_points.c | 176 +++++++++++++++++++++
.../injection_points/sql/injection_points.sql | 20 +++
src/tools/pgindent/typedefs.list | 1 +
5 files changed, 285 insertions(+)