document new env vars

README.md

@@ -25,6 +25,10 @@ Check and, if you would like, change the following environment variables for the
 | NEXUS_PORT             | Port of Nexus OSS                                                                                                                                |
 | NEXUS_PATH             | [Context path](https://help.sonatype.com/en/configuring-the-runtime-environment.html#changing-the-context-path) of Nexus OSS. Only used if the Nexus is hosted behind a reverse proxy with a URL like `https://your_url.domain/nexus/`. If not defined, the base URI remains `/`.                                                                                                                              |
 | ENTR_FALLBACK          | If defined, don't use `entr` to check for allowlist updates (this will be less reactive but we have found `entr` to not work in some situations) |
+| PYPI_REMOTE_URL        | URL of the PYPI Remote repository (`https://pypi.org/` by default) |
+| CRAN_REMOTE_URL        | URL of the CRAN Remote repository (`https://cran.r-project.org/` by default) |
+| APT_REMOTE_URL         | URL of the APT Remote repository (`http://deb.debian.org/debian` by default) |
+| APT_DISTRO             | Name of the APT distribution (`bookworm` by default) |
 
 Example allowlist files are included in the repository for [PyPI](allowlists/pypi.allowlist), [CRAN](allowlists/cran.allowlist) and [APT](allowlists/apt.allowlist).
 The PyPI allowlist includes numpy, pandas, matplotlib and their dependencies.