Include header to fix sqlite3_prepare_v2_fuzzer build on Windows

Include <cctype> since it declares std::toupper, in order to fix build
breakage on Windows.

Bug: 891867
Change-Id: I856286b390e152592951ccb318ec2260a6514073
Reviewed-on: https://chromium-review.googlesource.com/c/1259828
Commit-Queue: Victor Costan <pwnall@chromium.org>
Reviewed-by: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#596693}

third_party/sqlite/fuzz/sqlite3_prepare_v2_fuzzer.cc

@@ -7,6 +7,7 @@
 
 #include <algorithm>
 #include <array>
+#include <cctype>
 #include <string>
 #include <vector>