Wrong libpython configuration after changing python dir on Linux

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I want to make a portable app with PyCall included, so I move conda into a common folder (this folder I would later copy to another machine when deploying compiled app binaries):
```
sudo cp -rf ~/.julia/conda /opt/conda
```

Then I rebuild PyCall and make sure all conda and python-related paths (there are much of them!) point to the right place:
```julia
julia -e 'import Pkg;
ENV["CONDA_JL_HOME"] = "/opt/conda/3";
ENV["PYTHON"] = "/opt/conda/3/bin/python3.9";
Pkg.add("PyCall");
Pkg.build("PyCall");

using PyCall
@info(
"Conda.jl and PyCall.jl configuration after build, BUT wrong libpython!",
PyCall.Conda.ROOTENV,
PyCall.Conda.MINICONDA_VERSION,
PyCall.Conda.deps_file,
PyCall.Conda.PREFIX,
PyCall.Conda.BINDIR,
PyCall.Conda.LIBDIR,
PyCall.Conda.SCRIPTDIR,
PyCall.Conda.PYTHONDIR,
PyCall.Conda.conda,
PyCall.Conda.CONDARC,
PyCall.PYTHONHOME,
PyCall.libpython
)
'
```

Which gives me all paths set right but `PyCall.libpython`, which prevents me from running my compiled app on another machine: (also, I'm not sure about colons in `PyCall.PYTHONHOME`)
```
┌ Info: Conda.jl and PyCall.jl configuration after build, BUT wrong libpython!
│ PyCall.Conda.ROOTENV = "/opt/conda/3"
│ PyCall.Conda.MINICONDA_VERSION = "3"
│ PyCall.Conda.deps_file = "/home/root2/.julia/packages/Conda/x2UxR/src/../deps/deps.jl"
│ PyCall.Conda.PREFIX = "/opt/conda/3"
│ PyCall.Conda.BINDIR = "/opt/conda/3/bin"
│ PyCall.Conda.LIBDIR = "/opt/conda/3/lib"
│ PyCall.Conda.SCRIPTDIR = "/opt/conda/3/bin"
│ PyCall.Conda.PYTHONDIR = "/opt/conda/3/bin"
│ PyCall.Conda.conda = "/opt/conda/3/bin/conda"
│ PyCall.Conda.CONDARC = "/opt/conda/3/condarc-julia.yml"
│ PyCall.PYTHONHOME = "/opt/conda/3:/opt/conda/3"
└ PyCall.libpython = "/home/root2/.julia/conda/3/lib/libpython3.9.so.1.0"
```

Contents of deps.jl:
```bash
$ cat /home/root2/.julia/packages/Conda/x2UxR/src/../deps/deps.jl
const ROOTENV = "/opt/conda/3"
const MINICONDA_VERSION = "3"
const USE_MINIFORGE = true
const CONDA_EXE = "/opt/conda/3/bin/conda"
```

Start by reproducing the configuration with Pkg.build("PyCall") and inspect the generated deps.jl alongside PyCall.Conda.libpython and PyCall.PYTHONHOME. Trace where PyCall.libpython is selected after the conda directory changes; done means it resolves under /opt/conda/3 and the portable compiled app can run on another machine.

Written by the indexing model from the issue text.