refactor: Rename ripple namespace to xrpl (#5982)

This change renames all occurrences of `namespace ripple` and `ripple::` to `namespace xrpl` and `xrpl::`, respectively, as well as the names of test suites. It also provides a script to allow developers to replicate the changes in their local branch or fork to avoid conflicts.

src/libxrpl/protocol/STParsedJSON.cpp

@@ -41,7 +41,7 @@
 #include <type_traits>
 #include <utility>
 
-namespace ripple {
+namespace xrpl {
 
 namespace STParsedJSONDetail {
 template <typename U, typename S>
@@ -1190,4 +1190,4 @@ STParsedJSONObject::STParsedJSONObject(
     object = parseObject(name, json, sfGeneric, 0, error);
 }
 
-}  // namespace ripple
+}  // namespace xrpl