Merge pull request #2016 from typhoonzero/fix1995

Delete paddle/dist before build

paddle/scripts/docker/build.sh

@@ -21,6 +21,8 @@ cd /paddle/build
 
 # build script will not fail if *.deb does not exist
 rm *.deb 2>/dev/null || true
+# delete previous built whl packages
+rm -rf /paddle/paddle/dist 2>/dev/null || true
 
 cat <<EOF
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