README: Remove appveyor build badge. (#4584)

Bot failures are unrelated. 

1 files changed, 0 insertions, 1 deletions

diff --git a/README.md b/README.md
index 3a309bf51..f53db1656 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,6 @@ headers, and XML registry.
 
 ## Downloads
 
-[![Build status](https://ci.appveyor.com/api/projects/status/gpue87cesrx3pi0d/branch/master?svg=true)](https://ci.appveyor.com/project/Khronoswebmaster/spirv-tools/branch/master)
 <img alt="Linux" src="kokoro/img/linux.png" width="20px" height="20px" hspace="2px"/>[![Linux Build Status](https://storage.googleapis.com/spirv-tools/badges/build_status_linux_clang_release.svg)](https://storage.googleapis.com/spirv-tools/badges/build_link_linux_clang_release.html)
 <img alt="MacOS" src="kokoro/img/macos.png" width="20px" height="20px" hspace="2px"/>[![MacOS Build Status](https://storage.googleapis.com/spirv-tools/badges/build_status_macos_clang_release.svg)](https://storage.googleapis.com/spirv-tools/badges/build_link_macos_clang_release.html)
 <img alt="Windows" src="kokoro/img/windows.png" width="20px" height="20px" hspace="2px"/>[![Windows Build Status](https://storage.googleapis.com/spirv-tools/badges/build_status_windows_release.svg)](https://storage.googleapis.com/spirv-tools/badges/build_link_windows_vs2017_release.html)