refactor: Fix bugprone-string-constructor warning

src/.clang-tidy

@@ -2,6 +2,7 @@ Checks: '
 -*,
 bitcoin-*,
 bugprone-argument-comment,
+bugprone-string-constructor,
 bugprone-use-after-move,
 bugprone-lambda-function-name,
 misc-unused-using-decls,

src/wallet/db.cpp

@@ -129,9 +129,9 @@ bool IsSQLiteFile(const fs::path& path)
 
     file.close();
 
-    // Check the magic, see https://sqlite.org/fileformat2.html
+    // Check the magic, see https://sqlite.org/fileformat.html
     std::string magic_str(magic, 16);
-    if (magic_str != std::string("SQLite format 3", 16)) {
+    if (magic_str != std::string{"SQLite format 3\000", 16}) {
         return false;
     }