chore(postgresql): add pgadmin article to the knowledge bunch

knowledge base/pgadmin.md

@@ -0,0 +1,66 @@
+# pgAdmin
+
+Browser-based management tool for [PostgreSQL].
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+<details>
+  <summary>Setup</summary>
+
+```sh
+brew install --cask 'pgadmin4'
+docker pull 'dpage/pgadmin4'
+```
+
+</details>
+
+<!-- Uncomment if used
+<details>
+  <summary>Usage</summary>
+
+```sh
+```
+
+</details>
+-->
+
+<!-- Uncomment if used
+<details>
+  <summary>Real world use cases</summary>
+
+```sh
+```
+
+</details>
+-->
+
+## Further readings
+
+- [Website]
+- [Codebase]
+- [PostgreSQL]
+
+### Sources
+
+- [Documentation]
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[postgresql]: postgresql.md
+
+<!-- Files -->
+<!-- Upstream -->
+[codebase]: https://github.com/pgadmin-org/pgadmin4
+[documentation]: https://www.pgadmin.org/docs/
+[website]: https://www.pgadmin.org/
+
+<!-- Others -->

knowledge base/postgresql.md

@@ -221,6 +221,8 @@ psql -h 'localhost' -p '6543' -U 'postgres' -d 'postgres' -W
 - [pgxn-manager]
 - [dverite/postgresql-functions]
 - [MySQL]
+- [pg_flo]
+- [pgAdmin]
 
 ### Sources
 
@@ -245,6 +247,8 @@ psql -h 'localhost' -p '6543' -U 'postgres' -d 'postgres' -W
 
 <!-- Knowledge base -->
 [mysql]: mysql.md
+[pg_flo]: pg_flo.md
+[pgadmin]: pgadmin.md
 [sql]: sql.md
 
 <!-- Upstream -->