feat(bigtable): place the code after IsEmptyRowKey()

Author: drona-gyawali

google/cloud/bigtable/internal/google_bytes_traits.h

@@ -38,12 +38,12 @@ namespace internal {
 /// Return true if the row key is empty.
 inline bool IsEmptyRowKey(std::string const& key) { return key.empty(); }
 
-/// Clear the row key.
-inline void Clear(std::string& key) { key.clear(); }
-
 /// Return true if the row key is empty.
 inline bool IsEmptyRowKey(char const* key) { return std::string{} == key; }
 
+/// Clear the row key.
+inline void Clear(std::string& key) { key.clear(); }
+
 #if GOOGLE_CLOUD_CPP_CPP_VERSION >= 201703L
 /// Return true if the row key is empty.
 inline bool IsEmptyRowKey(std::string_view key) { return key.empty(); }