Bump dotenv-rails from 2.7.5 to 2.7.6

Bumps [dotenv-rails](https://github.com/bkeepers/dotenv) from 2.7.5 to 2.7.6.
- [Release notes](https://github.com/bkeepers/dotenv/releases)
- [Changelog](https://github.com/bkeepers/dotenv/blob/master/Changelog.md)
- [Commits](bkeepers/dotenv@v2.7.5...v2.7.6)

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

Gemfile.lock

@@ -115,10 +115,10 @@ GEM
       warden (~> 1.2.3)
     diff-lcs (1.3)
     docile (1.3.2)
-    dotenv (2.7.5)
-    dotenv-rails (2.7.5)
-      dotenv (= 2.7.5)
-      railties (>= 3.2, < 6.1)
+    dotenv (2.7.6)
+    dotenv-rails (2.7.6)
+      dotenv (= 2.7.6)
+      railties (>= 3.2)
     eco (1.0.0)
       coffee-script
       eco-source