PDM self update leaves wrong misleading output

[noudin-ledger]

• I have searched the issue tracker and believe that this is not a duplicate.

Steps to reproduce

• PDM is in version X and can be upgraded to PDM version Y.

[...]
PDM 2.2.1 is installed, while 2.3.2 is available.
Please run `pdm self update` to upgrade.
Run `pdm config check_update false` to disable the check.
pdm sync  11,61s user 1,43s system 126% cpu 10,329 total```

 * run `pdm self update`

## Actual behavior

 * It still outputs that it's in the wrong version.
```pdm self update
Installing version 2.3.2 succeeds.

PDM 2.2.1 is installed, while 2.3.2 is available.
Please run `pdm self update` to upgrade.
Run `pdm config check_update false` to disable the check.

Expected behavior

• It should not output this information, as it let user think that the upgrade failed.

Environment Information

PDM version:
  2.3.2
Python Interpreter:
  /home/noudin/LedgerVault/hsm-gateway/.venv/bin/python (3.10)
Project Root:
  /home/noudin/LedgerVault/hsm-gateway
Project Packages:
  None
{
  "implementation_name": "cpython",
  "implementation_version": "3.10.4",
  "os_name": "posix",
  "platform_machine": "x86_64",
  "platform_release": "5.15.0-56-generic",
  "platform_system": "Linux",
  "platform_version": "#62~20.04.1-Ubuntu SMP Tue Nov 22 21:24:20 UTC 2022",
  "python_full_version": "3.10.4",
  "platform_python_implementation": "CPython",
  "python_version": "3.10",
  "sys_platform": "linux"
}

I have the feeling that the version number is not updated in the client and this log should not be displayed when running the self update command.