Impl GhApiClient and use it in cargo-binstall to speedup resolution process (#832)

Fixed #776

 - Add new feature gh-api-client to binstalk-downloader
 - Impl new type `binstalk_downloader::remote::{RequestBuilder, Response}`
 - Impl `binstalk_downloader::gh_api_client::GhApiClient`, exposed if `cfg(feature = "gh-api-client")` and add e2e and unit tests for it
 - Use `binstalk_downloader::gh_api_client::GhApiClient` to speedup `cargo-binstall`
 - Add new option `--github-token` to supply the token for GitHub restful API, or read from env variable `GITHUB_TOKEN` if not present.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

.github/workflows/ci.yml

@@ -56,6 +56,8 @@ jobs:
     - run: just toolchain
     - run: just ci-install-deps
     - run: just test
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
   linux-cross-check:
     strategy:

.github/workflows/release-build.yml

@@ -56,6 +56,8 @@ jobs:
     - name: Ensure release binary is runnable
       if: "matrix.r"
       run: just e2e-tests
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
     - if: inputs.publish
       name: Upload to release