Add fuzz seeds for upstream/sqlite postfix colon

fuzz/fuzz_seeds/sqlite_2613_colon_traversal.sql

diff --git a/fuzz/fuzz_seeds/sqlite_2613_colon_traversal.sql b/fuzz/fuzz_seeds/sqlite_2613_colon_traversal.sql
new file mode 100644
index 0000000..346ddc8
--- /dev/null
+++ b/fuzz/fuzz_seeds/sqlite_2613_colon_traversal.sql
@@ -0,0 +1 @@
+SELECT a:b, :xxx FROM t;