synchronize concurrent access to map in test

GetRuntimeAddresses/symbolyze/gdb_test.go

@@ -7,6 +7,7 @@ import (
 	"os/exec"
 	"regexp"
 	"strconv"
+	"sync"
 	"testing"
 )
 
@@ -35,9 +36,12 @@ func TestSimpleGDB(t *testing.T) {
 	}
 
 	scanner := NewScanner("_PyRuntime", "*python3*")
+	var m sync.Mutex
 	scanner.OnFound(func(pid int, offset uint64) error {
 		t.Logf("scanner setting pid %d to offset %x", pid, offset)
+		m.Lock()
 		ourResults[pid] = offset
+		m.Unlock()
 		return nil
 	})