Revert "Upgrade to go 1.19 and update dependencies (#3069)" (#3085)

This reverts commit bba7c23957.

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_vtable.go

@@ -19,7 +19,7 @@ package sqlite3
 #cgo CFLAGS: -Wno-deprecated-declarations
 
 #ifndef USE_LIBSQLITE3
-#include "sqlite3-binding.h"
+#include <sqlite3-binding.h>
 #else
 #include <sqlite3.h>
 #endif
@@ -472,21 +472,10 @@ func goVBestIndex(pVTab unsafe.Pointer, icp unsafe.Pointer) *C.char {
 	}
 
 	info.idxNum = C.int(res.IdxNum)
-	info.idxStr = (*C.char)(C.sqlite3_malloc(C.int(len(res.IdxStr) + 1)))
-	if info.idxStr == nil {
-		// C.malloc and C.CString ordinarily do this for you. See https://golang.org/cmd/cgo/
-		panic("out of memory")
-	}
-	info.needToFreeIdxStr = C.int(1)
-
-	idxStr := *(*[]byte)(unsafe.Pointer(&reflect.SliceHeader{
-		Data: uintptr(unsafe.Pointer(info.idxStr)),
-		Len:  len(res.IdxStr) + 1,
-		Cap:  len(res.IdxStr) + 1,
-	}))
-	copy(idxStr, res.IdxStr)
-	idxStr[len(idxStr)-1] = 0 // null-terminated string
-
+	idxStr := C.CString(res.IdxStr)
+	defer C.free(unsafe.Pointer(idxStr))
+	info.idxStr = idxStr
+	info.needToFreeIdxStr = C.int(0)
 	if res.AlreadyOrdered {
 		info.orderByConsumed = C.int(1)
 	}