feat(bigtable):replace the code placement

Signed-off-by: Dorna Raj Gyawali <dronarajgyawali@gmail.com>

Author: drona-gyawali

google/cloud/bigtable/internal/google_bytes_traits.h

@@ -41,14 +41,14 @@ inline bool IsEmptyRowKey(std::string const& key) { return key.empty(); }
 /// 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(); }
 #endif  // GOOGLE_CLOUD_CPP_CPP_VERSION >= 201703L
 
+/// Clear the row key.
+inline void Clear(std::string& key) { key.clear(); }
+
 /// Return `< 0` if `lhs < rhs`, 0 if `lhs == rhs`, and `> 0' otherwise.
 inline int CompareRowKey(std::string const& lhs, std::string const& rhs) {
   return lhs.compare(rhs);