Limit build test suite to 'main' like in mariadb-10.3 (Closes: #920854)

Also skip unstable rpl tests, as is also done in mariadb-10.3 packaging.

debian/rules

@@ -101,7 +101,7 @@ override_dh_auto_test:
 	[ ! -f debian/unstable-tests.$(DEB_HOST_ARCH) ] || cat debian/unstable-tests.$(DEB_HOST_ARCH) >> mysql-test/unstable-tests
 	# Run testsuite
 ifeq (,$(filter nocheck,$(DEB_BUILD_OPTIONS)))
-	cd $(BUILDDIR)/mysql-test && ./mtr --force --testcase-timeout=30 --suite-timeout=540 --retry=3 --parallel=$(NUMJOBS) --skip-test-list=unstable-tests  || $(TESTSUITE_FAIL_CMD) ;
+	cd $(BUILDDIR)/mysql-test && ./mtr --force --testcase-timeout=30 --suite-timeout=540 --retry=3 --parallel=$(NUMJOBS) --skip-rpl --suite=main --skip-test-list=unstable-tests  || $(TESTSUITE_FAIL_CMD) ;
 endif
 
 override_dh_auto_install: