postgresqlTestHook: shutdown on failure

Previously, the user of postgresqlTestHook would have needed to set
failureHook accordingly. However, this was not a clean solution, because
postgresqlStop would also run for configure or build failures, before
the server was even started. This gave odd errors from a failed shutdown
in the log.

Now postgresqlStop is only called when it makes sense - and whenever
postgresqlTestHook is used.

pkgs/by-name/po/postgresqlTestHook/postgresql-test-hook.sh

···
-preCheckHooks+=('postgresqlStart')
-postCheckHooks+=('postgresqlStop')
+preCheckHooks+=(postgresqlStart)
+postCheckHooks+=(postgresqlStop)
 
 
 postgresqlStart() {
···
 
   echo 'starting postgresql'
   eval "${postgresqlStartCommands:-pg_ctl start}"
+  failureHooks+=(postgresqlStop)
 
   echo 'setting up postgresql'
   eval "$postgresqlTestSetupCommands"
···
 postgresqlStop() {
   echo 'stopping postgresql'
   pg_ctl stop
+  failureHooks=("${failureHooks[@]/postgresqlStop}")
 }

pkgs/servers/sql/postgresql/ext/pgtap.nix

···
       SELECT * FROM finish();
       ROLLBACK;
     '';
-    failureHook = "postgresqlStop";
     checkPhase = ''
       runHook preCheck
       psql -a -v ON_ERROR_STOP=1 -f $sqlPath

pkgs/servers/sql/postgresql/ext/postgis.nix

···
   ];
 
   postgresqlTestUserOptions = "LOGIN SUPERUSER";
-  failureHook = "postgresqlStop";
 
   # postgis config directory assumes /include /lib from the same root for json-c library
   env.NIX_LDFLAGS = "-L${lib.getLib json_c}/lib";

pkgs/servers/sql/postgresql/postgresqlTestExtension.nix

···
       postgresqlTestHook
       (postgresql.withPackages (ps: [ finalPackage ] ++ (map (p: ps."${p}") withPackages)))
     ];
-    failureHook = "postgresqlStop";
     postgresqlTestUserOptions = "LOGIN SUPERUSER";
     passAsFile = [ "sql" ];
     sql =