chore(rust): Update Rust PrintAST Meta-->PathMeta

Author: data-douser

server/ql/rust/tools/test/PrintAST/PrintAST.expected

@@ -159,7 +159,7 @@ Example1.rs:
 #   24|                               getExpr(1): [IntegerLiteralExpr] 2
 #   24|                               getExpr(2): [IntegerLiteralExpr] 3
 #   24|                           getAttr(0): [Attr] Attr
-#   24|                             getMeta(): [Meta] Meta
+#   24|                             getMeta(): [PathMeta] PathMeta
 #   24|                               getPath(): [Path] rustc_box
 #   24|                                 getSegment(): [PathSegment] rustc_box
 #   24|                                   getIdentifier(): [NameRef] rustc_box