Revert "Add comment referring to bazelbuild/bazel#24829"

This reverts commit 61c3f7c.

This comment is wrong, see https://groups.google.com/g/bazel-discuss/c/vGWAMaziGCU/m/bt5Uu7TDAQAJ:

    Module extensions aren't meant to replace repository rules - in fact, module extensions can create repositories only
    by instantiating repository rules. The files created by a module extension's implementation function are only kept in a
    temporary location. It is thus both perfectly fine and necessary to continue to use repository rules and orchestrate
    them via module extensions.

elisp/extensions.bzl

@@ -1,4 +1,4 @@
-# Copyright 2023, 2024, 2025 Google LLC
+# Copyright 2023, 2024 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -70,7 +70,7 @@ def _elisp_http_archive_impl(ctx):
     """Implementation of the `elisp_http_archive` repository rule."""
     ctx.download_and_extract(
         url = ctx.attr.urls,
-        integrity = ctx.attr.integrity,
+        integrity = ctx.attr.integrity or fail("missing archive checksum"),
         stripPrefix = ctx.attr.strip_prefix,
     )
     ctx.template(
@@ -84,9 +84,6 @@ def _elisp_http_archive_impl(ctx):
         executable = False,
     )
 
-# FIXME: Remove this rule and inline its implementation once
-# https://github.com/bazelbuild/bazel/issues/24829 is fixed in all supported
-# versions of Bazel.
 _elisp_http_archive = repository_rule(
     doc = _HTTP_ARCHIVE_DOC.format(kind = "repository rule"),
     attrs = _HTTP_ARCHIVE_ATTRS | {
@@ -102,7 +99,7 @@ def _elisp_impl(ctx):
             _elisp_http_archive(
                 name = arch.name,
                 urls = arch.urls,
-                integrity = arch.integrity or fail("missing archive checksum"),
+                integrity = arch.integrity,
                 strip_prefix = arch.strip_prefix,
                 target_name = arch.target_name,
                 exclude = arch.exclude,