Bazel: update link to Bazel's homepage.

Change-Id: Ic4b1fd074bba967b9ae9d73ad4a7238dbb5d5c4f
Signed-off-by: Piotr Sikora <piotrsikora@google.com>
Reviewed-on: https://nginx-review.googlesource.com/2600
Reviewed-by: Gurgen Hrachyan <gugo@google.com>

README.md

diff --git a/README.md b/README.md
index 155b22e..ffbfe07 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 
 ## Building
 
-To build `nginx` binary with [Bazel](https://bazel.io):
+To build `nginx` binary with [Bazel](https://bazel.build):
 
     $ bazel build :nginx