fix(build): add docker config (#20)

tpoisonooo · megvii-mge · web-flow · commit 68140ef70c16 · 2021-09-19T17:55:59.000+08:00
Co-authored-by: MegEngine &lt;megengine@megvii.com&gt;
diff --git a/ci/cargo-config b/ci/cargo-config
@@ -0,0 +1,5 @@
+[source.crates-io]
+replace-with = 'tuna'
+
+[source.tuna]
+registry = "https://mirrors.tuna.tsinghua.edu.cn/git/crates.io-index.git"
