fix(pipstar): actually pass the extras down the call stack (#3468)

It seems that the extras were not correctly passed down the call stack.
The upstream code was handling everything correctly and we had unit
tests for the downstream code.

Fixes #3352

python/private/pypi/BUILD.bazel

diff --git a/python/private/pypi/BUILD.bazel b/python/private/pypi/BUILD.bazel
index 18caa53..aa96cf8 100644
--- a/python/private/pypi/BUILD.bazel
+++ b/python/private/pypi/BUILD.bazel
@@ -433,6 +433,7 @@
         ":generate_whl_library_build_bazel_bzl",
         ":parse_whl_name_bzl",
         ":patch_whl_bzl",
+        ":pep508_requirement_bzl",
         ":pypi_repo_utils_bzl",
         ":whl_metadata_bzl",
         ":whl_target_platforms_bzl",

python/private/pypi/whl_library.bzl

diff --git a/python/private/pypi/whl_library.bzl b/python/private/pypi/whl_library.bzl
index 201ef59..9f04252 100644
--- a/python/private/pypi/whl_library.bzl
+++ b/python/private/pypi/whl_library.bzl
@@ -24,6 +24,7 @@
 load(":generate_whl_library_build_bazel.bzl", "generate_whl_library_build_bazel")
 load(":parse_whl_name.bzl", "parse_whl_name")
 load(":patch_whl.bzl", "patch_whl")
+load(":pep508_requirement.bzl", "requirement")
 load(":pypi_repo_utils.bzl", "pypi_repo_utils")
 load(":whl_metadata.bzl", "whl_metadata")
 load(":whl_target_platforms.bzl", "whl_target_platforms")
@@ -435,6 +436,7 @@
             group_deps = rctx.attr.group_deps,
             group_name = rctx.attr.group_name,
             namespace_package_files = namespace_package_files,
+            extras = requirement(rctx.attr.requirement).extras,
         )
     else:
         target_platforms = rctx.attr.experimental_target_platforms or []