The external traffic policy terminating endpoints test was testing
LoadBalancer functionality against a NodePort service with no
nodePorts (or loadBalancer IPs). It managed to test what it wanted to
test, but it's kind of dubious (and we probably _shouldn't_ have been
generating the rules it was looking for since there was no way to
actually reach the XLB chains). So fix that.
Also make the terminating endpoints test use session affinity, to add
more testing for that. Also, remove the multiple copies of the same
identical Service that is used for all of the test cases in that test.
Also add a "Cluster traffic policy and no source ranges" test to
TestOverallIPTablesRulesWithMultipleServices since we weren't really
testing either of those.
Also add a test of --masquerade-all.
6ab3dc6875