Python feature (os-provided) installation failed if python already installed

When I tried to install Python on the rust image, the build failed with an error because it could not create a symbolic link.

```log
#0 48.02 ln: failed to create symbolic link '/usr/bin/python': File exists
#0 48.02 ERROR: Feature "Python" (ghcr.io/devcontainers/features/python) failed to install! Look at the documentation at https://github.com/devcontainers/features/tree/main/src/python for help troubleshooting this error.
```

My devcontainer.json is this.

```json
{
"name": "${localWorkspaceFolderBasename}",
"image": "mcr.microsoft.com/devcontainers/rust:1",
"runArgs": ["--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined"],

"customizations": {
"vscode": {
"settings": {
"lldb.executable": "/usr/bin/lldb",
"files.watcherExclude": {
"**/target/**": true
},
"rust-analyzer.checkOnSave.command": "clippy"
},
"extensions": [
"vadimcn.vscode-lldb",
"mutantdino.resourcemonitor",
"rust-lang.rust-analyzer",
"tamasfe.even-better-toml",
"serayuzgur.crates"
]
}
},
"remoteUser": "vscode",
"features": {
"ghcr.io/devcontainers/features/python:1": {}
}
}
```

Overwrite the symbolic link, or, I think it is better to stop with an error immediately after executing the script (instead of stopping after some time has passed)