[TypeChecker] NFC: Complicate perf test-case expression by adding more operators

This test has become flaky in different configurations due to a varying
number of available operator overloads, let's use more operators to make
sure that it's "too complex" regardless of configuration.

Resolves: rdar://77656775

Author: xedin

validation-test/Sema/type_checker_perf/slow/rdar19737632.swift

@@ -1,11 +1,10 @@
 // RUN: %target-typecheck-verify-swift -solver-expression-time-threshold=1
 // REQUIRES: tools-release,no_asan
 
-// rdar://77656775
-// UNSUPPORTED: CPU=arm64 && OS=macosx
-
 let a = "a"
 let b = "b"
 let c = 42
-_ = "a=" + a + ";b=" + b + ";c=" + c
+let d = 0.0
+
+_ = "a=" + a + ";b=" + b + ";c=" + c + ";d=" + d
 // expected-error@-1 {{reasonable time}}