Update README.md

Fix build status icon markdown.

README.md

diff --git a/README.md b/README.md
index c9621e6..e542b40 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Process
 
-[![Build Status - Cirrus][]][Build status]
+![Build Status - Cirrus][]
 
 A process runner for Dart that uses the
 [`ProcessManager`](https://github.com/google/process.dart/blob/master/lib/src/interface/process_manager.dart#L21)
@@ -43,4 +43,4 @@
   }
 ```
 
-[Build Status - Cirrus]: https://api.cirrus-ci.com/github/google/process_runner.svg
\ No newline at end of file
+[Build Status - Cirrus]: https://api.cirrus-ci.com/github/google/process_runner.svg