Add the repo rule `http_jar`

Copybara Import from https://github.com/bazelbuild/rules_java/pull/238

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Add the repo rule `http_jar` (#238)

The repo rule `http_jar` currently lives in `@bazel_tools`, which results in an implicit dependency on `rules_java` because it creates a repo with a BUILD file that uses `java_import`. So this repo rule really belongs in `rules_java`.

This PR copies it over from `@bazel_tools//tools/build_defs/repo:http.bzl` with minimal edits.

Closes #238
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COPYBARA_INTEGRATE_REVIEW=https://github.com/bazelbuild/rules_java/pull/238 from bazelbuild:wyv-http-jar 74d325a744cd7333e8669685d3ea1d3112a5078c
PiperOrigin-RevId: 693270198
Change-Id: I44f6d60301f27db8515243af54f79cb0ab4a7c0c