Bug 20985 – std.socket random failures due to environment socket.d(1004)

--- std.socket(999) test fails depending on environment --- (core.exception.AssertError@std/socket.d(1004): Assertion failure ---------------- ??:? onAssertError [0x8054158c0] ??:? _d_assertp [0x805415b5a] ??:? @safe void std.socket.__unittest_L997_C7().__lambda1() [0x8036c89c2] ??:? @trusted void std.socket.softUnittest(void delegate() @safe, int) [0x8036c6f71] ??:? @safe void std.socket.__unittest_L997_C7() [0x8036c884e] ??:? void std.socket.__modtest() [0x8036e92e1] ../druntime/src/test_runner.d:73 int test_runner.testAll().__foreachbody1(object.ModuleInfo*) [0x4019c3] ../druntime/src/test_runner.d:44 core.runtime.UnitTestResult test_runner.tester() [0x4018cf] ../druntime/src/test_runner.d:25 core.runtime.UnitTestResult test_runner.tester() [0x401707] ??:? runModuleUnitTests [0x805416a76] ??:? void rt.dmain2._d_run_main2(char[][], ulong, extern (C) int function(char[][])*).runAll() [0x805445859] ??:? void rt.dmain2._d_run_main2(char[][], ulong, extern (C) int function(char[][])*).tryExec(scope void delegate()) [0x8054457d4] ??:? _d_run_main2 [0x80544573b] ??:? _d_run_main [0x80544546a] ../druntime/import/core/internal/entrypoint.d:29 _Dmain [0x401c0d])

*** This issue has been marked as a duplicate of issue 21114 ***