- Remove patch which is not needed anymore:
* 0001-bazel-Use-http_archive-instead-of-git_repository.patch

- Update to version 0.20.3:
* Support go1.13.5, 1.12.14 (#2308)
* tests/legacy/trans_dep_error: delete test (#2303)
* Migrate reproducibility test to go_bazel_test (#2299)
* Clear GOPATH in go_context (#2291)
* nogo: defer wg.Done() (#2300)
* Remove //tests/legacy/cgo_library_root_dir (#2297)
* Migrate legacy test to //tests/core/go_test:test_filter_test (#2298)
* Migrate legacy tests to //tests/core/go_download_sdk (a go_bazel_test) (#2296)
* Use bash from the environment instead of absolute path (#2295)
* Migrate //tests/core/race to go_bazel_test (#2293)
* tests/core/nogo: migrate to go_bazel_test (#2289)
* tests/core/coverage: migrate to go_bazel_test (#2288)
* go/tools/bazel_testing: support location args without external prefix (#2287)
* Add SetUp method to Args for go_bazel_test (#2282)
* Add support for dirs in txtar expander (#2280)
* Conditionally include Bazel testing library only if needed (#2279)
* go_compat_repo: alias constraint values and settings to bazel_tools or platforms (#2275)
* skip directory matching in FindBinary (#2274)
* go_bazel_test: add test to ensure data and args keep working (#2248)
* delete unused cgoarc flag from compilepkg builder (#2264)
* Set RULES_GO_VERSION to 0.20.3
* Support go1.13.4, 1.12.13 (#2269)
* Set RULES_GO_VERSION to 0.20.2 (forwarded request 765216 from mrostecki)