[master] add testdata file to the distribution

I didn't test yet, but was missing and I see the
distcheck autobuilder had problem related to this.

src/lib/config/tests/testdata/Makefile.am

@@ -21,6 +21,7 @@ EXTRA_DIST += data22_6.data
 EXTRA_DIST += data22_7.data
 EXTRA_DIST += data22_8.data
 EXTRA_DIST += data22_9.data
+EXTRA_DIST += data22_10.data
 EXTRA_DIST += spec1.spec
 EXTRA_DIST += spec2.spec
 EXTRA_DIST += spec3.spec