Generate coverage across all sub-dirs (#7416)

buildscripts/go-coverage.sh

@@ -1,12 +1,6 @@
 #!/usr/bin/env bash
 
 set -e
-echo "" > coverage.txt
 
-for d in $(go list ./... | grep -v browser); do
-    CGO_ENABLED=0 go test -v -coverprofile=profile.out -covermode=atomic "$d"
-    if [ -f profile.out ]; then
-        cat profile.out >> coverage.txt
-        rm profile.out
-    fi
-done
+
+CGO_ENABLED=0 go test -v -coverprofile=coverage.txt -covermode=atomic ./...