Fixes#36168.
* Update `libpq` to 16.2.
* Removed outdated patch `python_lib.patch`.
* Feature `client` has an error on `x86-windows`:
https://github.com/microsoft/vcpkg/issues/36693, but it is not caused by
this update and will be solved in another PR.
- [x] Changes comply with the [maintainer
guide](https://github.com/microsoft/vcpkg-docs/blob/main/vcpkg/contributing/maintainer-guide.md).
- [x] SHA512s are updated for each updated download.
- [ ] ~The "supports" clause reflects platforms that may be fixed by
this new version.~
- [ ] ~Any fixed [CI
baseline](https://github.com/microsoft/vcpkg/blob/master/scripts/ci.baseline.txt)
entries are removed from that file.~
- [x] Any patches that are no longer applied are deleted from the port's
directory.
- [x] The version database is fixed by rerunning `./vcpkg x-add-version
--all` and committing the result.
- [x] Only one version is added to each modified port's versions file.
Features `client,icu,lz4,nls,openssl,python,tcl,xml,xslt,zlib,zstd` are
tested successfully in the following triplet:
```
x64-windows
x64-windows-static
```
Features `icu,lz4,nls,openssl,xml,xslt,zlib,zstd` are tested
successfully in the following triplet:
```
x86-windows
```
Features `readline,bonjour` are tested successfully in the following
triplet:
```
x64-osx
```
Feature `readline` are tested successfully in the following triplet:
```
x64-linux
```
The usage test passed on `x64-windows` (header files found):
```
The package libpq provides CMake integration:
find_package(PostgreSQL REQUIRED)
target_link_libraries(main PRIVATE PostgreSQL::PostgreSQL)
```
---------
Co-authored-by: Monica <v-liumonica@microsoft.com>
