Bump jekyll-feed from 0.15.1 to 0.16.0

Bumps [jekyll-feed](https://github.com/jekyll/jekyll-feed) from 0.15.1 to 0.16.0.
- [Release notes](https://github.com/jekyll/jekyll-feed/releases)
- [Changelog](https://github.com/jekyll/jekyll-feed/blob/master/History.markdown)
- [Commits](https://github.com/jekyll/jekyll-feed/compare/v0.15.1...v0.16.0)

---
updated-dependencies:
- dependency-name: jekyll-feed
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -40,9 +40,9 @@ GEM
       ruby-enum (~> 0.5)
     concurrent-ruby (1.1.9)
     crass (1.0.6)
-    em-websocket (0.5.2)
+    em-websocket (0.5.3)
       eventmachine (>= 0.12.9)
-      http_parser.rb (~> 0.6.0)
+      http_parser.rb (~> 0)
     erubi (1.10.0)
     ethon (0.15.0)
       ffi (>= 1.15.0)
@@ -64,7 +64,7 @@ GEM
       rainbow (~> 3.0)
       typhoeus (~> 1.3)
       yell (~> 2.0)
-    http_parser.rb (0.6.0)
+    http_parser.rb (0.8.0)
     i18n (1.8.11)
       concurrent-ruby (~> 1.0)
     jekyll (4.2.1)
@@ -94,7 +94,7 @@ GEM
       commonmarker (~> 0.17.6)
       jekyll-commonmark (~> 1.2)
       rouge (>= 2.0, < 4.0)
-    jekyll-feed (0.15.1)
+    jekyll-feed (0.16.0)
       jekyll (>= 3.7, < 5.0)
     jekyll-gist (1.5.0)
       octokit (~> 4.2)