postgresql@11: revision bump (perl 5.38.0)

```
brew linkage --test postgresql@11
  Missing libraries:
    unexpected (libperl.so)
```

found in:
- Homebrew#152259

relates to:
- Homebrew#145939

Signed-off-by: Rui Chen <[email protected]>

Author: chenrui333

Formula/p/[email protected]

@@ -4,6 +4,7 @@ class PostgresqlAT11 < Formula
   url "https://ftp.postgresql.org/pub/source/v11.21/postgresql-11.21.tar.bz2"
   sha256 "07b0837471d5dd77b25166b34718f3ba10816b6ad61e691e6fc547cf3fcff850"
   license "PostgreSQL"
+  revision 1
 
   livecheck do
     url "https://ftp.postgresql.org/pub/source/"