flake: postgresql connection reset

[spikecurtis]

Lots of errors of the form:

        	Error:      	Received unexpected error:
        	            	init default connection params:
        	            	    github.com/coder/coder/v2/coderd/database/dbtestutil.Open
        	            	        /home/runner/work/coder/coder/coderd/database/dbtestutil/postgres.go:153
        	            	  - open postgres connection:
        	            	    github.com/coder/coder/v2/coderd/database/dbtestutil.initDefaultConnection
        	            	        /home/runner/work/coder/coder/coderd/database/dbtestutil/postgres.go:115
        	            	  - read tcp 127.0.0.1:51624->127.0.0.1:5432: read: connection reset by peer

seen here: https://github.com/coder/coder/actions/runs/15643209058/job/44075283530

[spikecurtis]

We don't collect any PostgreSQL logs at present because we generally consider it fairly bulletproof. If this recurs we'll have to change that stance.