Suspicious prefix (not impeding correct behaviour)

### Solution to issue cannot be found in the documentation.

- [X] I checked the documentation.

### Issue

**Everything works fine, this is just aesthetics**

In running with ffmpeg-python 0.2.0 (and ffmpeg 5.1.0) on macOS/arm I'm getting an incorrect `--prefix` and `--pkg-config`:
```
offmpeg version 5.1 Copyright (c) 2000-2022 the FFmpeg developers
built with clang version 14.0.4
configuration: --prefix=/Users/runner/miniforge3/conda-bld/ffmpeg_1660921560116/_h_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_pl --cc=arm64-apple-darwin20.0.0-clang --cxx=arm64-apple-darwin20.0.0-clang++ --nm=arm64-apple-darwin20.0.0-nm --ar=arm64-apple-darwin20.0.0-ar --disable-doc --disable-openssl --enable-demuxer=dash --enable-hardcoded-tables --enable-libfreetype --enable-libfontconfig --enable-libopenh264 --enable-cross-compile --arch=arm64 --target-os=darwin --cross-prefix=arm64-apple-darwin20.0.0- --host-cc=/Users/runner/miniforge3/conda-bld/ffmpeg_1660921560116/_build_env/bin/x86_64-apple-darwin13.4.0-clang --enable-neon --enable-gnutls --enable-libmp3lame --enable-libvpx --enable-pthreads --enable-gpl --enable-libx264 --enable-libx265 --enable-libaom --enable-libsvtav1 --enable-libxml2 --enable-pic --enable-shared --disable-static --enable-version3 --enable-zlib --pkg-config=/Users/runner/miniforge3/conda-bld/ffmpeg_1660921560116/_build_env/bin/pkg-config
```
Neither

* `/Users/runner/miniforge3/conda-bld/ffmpeg_1660921560116/_h_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_pl`
* `/Users/runner/miniforge3/conda-bld/ffmpeg_1660921560116/_build_env/bin/pkg-config`

exists on my system.

### Installed packages

```shell
ffmpeg 5.1.0 gpl_hfdc7bce_101 conda-forge
ffmpeg-python 0.2.0 py_0 conda-forge
```

### Environment info

```shell
active environment : code_line
active env location : /Users/tdegeus/miniforge3/envs/code_line
shell level : 2
user config file : /Users/tdegeus/.condarc
populated config files : /Users/tdegeus/miniforge3/.condarc
/Users/tdegeus/.condarc
conda version : 4.14.0
conda-build version : not installed
python version : 3.9.13.final.0
virtual packages : __osx=12.5.1=0
__unix=0=0
__archspec=1=arm64
base environment : /Users/tdegeus/miniforge3 (writable)
conda av data dir : /Users/tdegeus/miniforge3/etc/conda
conda av metadata url : None
channel URLs : https://conda.anaconda.org/conda-forge/osx-arm64
https://conda.anaconda.org/conda-forge/noarch
https://repo.anaconda.com/pkgs/main/osx-arm64
https://repo.anaconda.com/pkgs/main/noarch
https://repo.anaconda.com/pkgs/r/osx-arm64
https://repo.anaconda.com/pkgs/r/noarch
package cache : /Users/tdegeus/miniforge3/pkgs
/Users/tdegeus/.conda/pkgs
envs directories : /Users/tdegeus/miniforge3/envs
/Users/tdegeus/.conda/envs
platform : osx-arm64
user-agent : conda/4.14.0 requests/2.28.1 CPython/3.9.13 Darwin/21.6.0 OSX/12.5.1
UID:GID : 503:20
netrc file : None
offline mode : False
```