Update README to point at new tag of shim-build
diff --git a/README.md b/README.md
index 7d148c2..8128f0b 100644
--- a/README.md
+++ b/README.md
@@ -64,7 +64,7 @@
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 What OS and toolchain must we use to reproduce this build?  Include where to find it, etc.  We're going to try to reproduce your build as close as possible to verify that it's really a build of the source tree you tell us it is, so these need to be fairly thorough. At the very least include the specific versions of gcc, binutils, and gnu-efi which were used, and where to find those binaries.
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-This repo contains the Dockerfile we use to build shim: https://github.com/neverware/shim-build
+This repo contains the Dockerfile we use to build shim: https://github.com/neverware/shim-build/tree/v2
 
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 Which files in this repo are the logs for your build?   This should include logs for creating the buildroots, applying patches, doing the build, creating the archives, etc.