Make it possible to grant self perfmissions to self created roles (#4821)

## Problem

See: https://neondb.slack.com/archives/C04USJQNLD6/p1689973957908869

## Summary of changes

Bump Postgres version 

## Checklist before requesting a review

- [ ] I have performed a self-review of my code.
- [ ] If it is a core feature, I have added thorough tests.
- [ ] Do we need to implement analytics? if so did you add the relevant
metrics to the dashboard?
- [ ] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.

## Checklist before merging

- [ ] Do not forget to reformat commit message to not include the above
checklist

---------

Co-authored-by: Konstantin Knizhnik <knizhnik@neon.tech>

vendor/revisions.json

@@ -1,4 +1,4 @@
 {
-    "postgres-v15": "e3fbfc4d143b2d3c3c1813ce747f8af35aa9405e",
-    "postgres-v14": "12c5dc8281d20b5bd636e1097eea80a7bc609591"
+    "postgres-v15": "1220c8a63f00101829f9222a5821fc084b4384c7",
+    "postgres-v14": "ebedb34d01c8ac9c31e8ea4628b9854103a1dc8f"
 }