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/test/jtx/impl/directory.cpp

@@ -2,7 +2,7 @@
 
 #include <xrpl/ledger/Sandbox.h>
 
-namespace ripple::test::jtx {
+namespace xrpl::test::jtx {
 
 /** Directory operations. */
 namespace directory {
@@ -123,4 +123,4 @@ adjustOwnerNode(ApplyView& view, uint256 key, std::uint64_t page)
 
 }  // namespace directory
 
-}  // namespace ripple::test::jtx
+}  // namespace xrpl::test::jtx