tests: Bluetooth: Mark generated qualification file as binaries

Those are generated files and shall not be modified to match codestyle
requirements.

Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>

tests/bluetooth/qualification/.gitattributes

@@ -0,0 +1,6 @@
+# Files generated by Bluetooth Qualification Workspace.
+# Those are XML that don't follow Zephyr style guidance but shall
+# not be modified since otherwise BT SIG tools are not able to
+# import them. Just treat them as binaries.
+*.pts binary
+*.bqw binary