Fix a typo in the bazel BUILD file (src vs srcs)

Change-Id: Ic53d2b62afcfbfd9d70a0b531185e265e71149fd
Signed-off-by: David Gow <davidgow@google.com>
diff --git a/BUILD.bazel b/BUILD.bazel
index 94e75a4..a6af0ed 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -60,7 +60,7 @@
 
 py_test(
     name = "lcov_parser_test",
-    src = ["lcov_parser/lcov_parser_test.py"],
+    srcs = ["lcov_parser/lcov_parser_test.py"],
     python_version = "PY3",
     deps = ["lcov_parser/lcov_parser.py"],
 )