[NFC] Tweaked memory verifier require messages.

Grammar.

Author: nate-chandler

lib/SIL/Verifier/MemoryLifetimeVerifier.cpp

@@ -562,15 +562,16 @@ void MemoryLifetimeVerifier::checkFunction(BitDataflow &dataFlow) {
         require(expectedReturnBits & ~bs.data.exitSet,
           "indirect argument is not alive at function return", term);
         require(bs.data.exitSet & ~expectedReturnBits & nonTrivialLocations,
-          "memory is initialized at function return but shouldn't", term,
-           /*excludeTrivialEnums*/ true);
+                "memory is initialized at function return but shouldn't be",
+                term,
+                /*excludeTrivialEnums*/ true);
         break;
       case SILInstructionKind::ThrowInst:
         require(expectedThrowBits & ~bs.data.exitSet,
           "indirect argument is not alive at throw", term);
         require(bs.data.exitSet & ~expectedThrowBits & nonTrivialLocations,
-          "memory is initialized at throw but shouldn't", term,
-           /*excludeTrivialEnums*/ true);
+                "memory is initialized at throw but shouldn't be", term,
+                /*excludeTrivialEnums*/ true);
         break;
       default:
         break;