.gitmodules: use the official Git URL w/o redirect

diff --git a/.gitmodules b/.gitmodules
index 53d17874924093c298f0f111f1c4c4d680c68f55..3533f0df5d1ce82d13e9aa992c7ee62798b5aa0c 100644 (file)
--- a/.gitmodules
+++ b/.gitmodules
@@ -25,4 +25,4 @@
        url = https://github.com/rust-lang-nursery/reference.git
 [submodule "book"]
        path = src/doc/book
-       url = https://github.com/rust-lang/book
+       url = https://github.com/rust-lang/book.git