[TypeChecker] NFC: Make test-case for rdar://19737632 more complex

Test-case as-is is producing conversion failure on Apple Silicon

Resolves: rdar://79414045

Author: xedin

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

@@ -5,6 +5,7 @@ let a = "a"
 let b = "b"
 let c = 42
 let d = 0.0
+let e: Float = 1.0
 
-_ = "a=" + a + ";b=" + b + ";c=" + c + ";d=" + d
+_ = "a=" + a + ";b=" + b + ";c=" + c + ";d=" + d + ";e=" + e
 // expected-error@-1 {{reasonable time}}