Change . to [^] because /s isn't well supported in JS

The `s` flag on the RegExp object informs the engine to treat a
dot character as a class that includes the newline character.
Without it newlines aren't considered in the dot.

Since this flag is new to Javascript and not well supported in
different browsers I have removed it in favor of an explicit class
of characters that _does_ include the newline, namely the open
exclusion of `[^]` which permits all input characters.

Hat-top to @Hywan for finding this.

lib/parser-rd-trampoline.js

@@ -6,7 +6,7 @@ let document;
 let offset;
 let output;
 let stack;
-const tokenizer = /<!--\s+(?<closer>\/)?wp:(?<namespace>[a-z][a-z0-9_-]*\/)?(?<name>[a-z][a-z0-9_-]*)\s+(?<attrs>{(?:(?!}\s+-->).)+}\s+)?(?<void>\/)?-->/gs;
+const tokenizer = /<!--\s+(?<closer>\/)?wp:(?<namespace>[a-z][a-z0-9_-]*\/)?(?<name>[a-z][a-z0-9_-]*)\s+(?<attrs>{(?:(?!}\s+-->)[^])+}\s+)?(?<void>\/)?-->/g;
 
 class Block {
 	constructor(name, attrs, innerBlocks, innerHTML) {