CDRIVER-2298 race in topology description test
CDRIVER-2298 race in topology description test

/TopologyDescription/readable_writable/pooled could fail if topology
discovered completed before the test asserted that there were no
writable servers.

jmikola/mongo-c-driver,remicollet/mongo-c-driver,beingmeta/mongo-c-driver,rcsanchez97/mongo-c-driver,remicollet/mongo-c-driver,acmorrow/mongo-c-driver,beingmeta/mongo-c-driver,rcsanchez97/mongo-c-driver,derickr/mongo-c-driver,mongodb/mongo-c-driver,beingmeta/mongo-c-driver,derickr/mongo-c-driver,jmikola/mongo-c-driver,jmikola/mongo-c-driver,remicollet/mongo-c-driver,ajdavis/mongo-c-driver,beingmeta/mongo-c-driver,remicollet/mongo-c-driver,mongodb/mongo-c-driver,mongodb/mongo-c-driver,acmorrow/mongo-c-driver,acmorrow/mongo-c-driver,beingmeta/mongo-c-driver,rcsanchez97/mongo-c-driver,remicollet/mongo-c-driver,rcsanchez97/mongo-c-driver,ajdavis/mongo-c-driver,jmikola/mongo-c-driver,derickr/mongo-c-driver,ajdavis/mongo-c-driver,mongodb/mongo-c-driver,jmikola/mongo-c-driver,beingmeta/mongo-c-driver,acmorrow/mongo-c-driver,ajdavis/mongo-c-driver,derickr/mongo-c-driver,acmorrow/mongo-c-driver,jmikola/mongo-c-driver,beingmeta/mongo-c-driver,jmikola/mongo-c-driver,ajdavis/mongo-c-driver,acmorrow/mongo-c-driver,mongodb/mongo-c-driver,beingmeta/mongo-c-driver,acmorrow/mongo-c-driver,rcsanchez97/mongo-c-driver,remicollet/mongo-c-driver,remicollet/mongo-c-driver,derickr/mongo-c-driver,mongodb/mongo-c-driver,mongodb/mongo-c-driver,derickr/mongo-c-driver,ajdavis/mongo-c-driver,derickr/mongo-c-driver,ajdavis/mongo-c-driver,rcsanchez97/mongo-c-driver,rcsanchez97/mongo-c-driver