Remove external/proguard from manifest

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Test: TreeHugger
Merged-In: I64c3b89fde2e0f4720b5074baed885e20496c43b
Merged-In: I0dcd15be3270e61fb4931ef8b979fc936c6b190c
Change-Id: I176e65b9095893568274ee091d62ae7bb74d77d2
diff --git a/default.xml b/default.xml
index 4fd5ec0..6bcec99 100644
--- a/default.xml
+++ b/default.xml
@@ -453,7 +453,6 @@
   <project path="external/pigweed" name="platform/external/pigweed" groups="pdk" />
   <project path="external/ply" name="platform/external/ply" groups="pdk" />
   <project path="external/ppp" name="platform/external/ppp" groups="pdk" />
-  <project path="external/proguard" name="platform/external/proguard" groups="pdk" />
   <project path="external/protobuf" name="platform/external/protobuf" groups="pdk" />
   <project path="external/psimd" name="platform/external/psimd" groups="pdk" />
   <project path="external/pthreadpool" name="platform/external/pthreadpool" groups="pdk" />