fix /proc test case for util::read_file

old-commit-hash: ea6f779b3e

selfdrive/common/tests/test_util.cc

@@ -20,9 +20,9 @@ std::string random_bytes(int size) {
 }
 
 TEST_CASE("util::read_file") {
-  SECTION("read /proc") {
-    std::string ret = util::read_file("/proc/self/cmdline");
-    REQUIRE(ret.find("test_util") != std::string::npos);
+  SECTION("read /proc/version") {
+    std::string ret = util::read_file("/proc/version");
+    REQUIRE(ret.find("Linux version") != std::string::npos);
   }
   SECTION("read file") {
     char filename[] = "/tmp/test_read_XXXXXX";