perf(snapshot): avoid recreate element a every time (#1387)

perf(snapshot): avoid costly generation of <a> element on each call to `getHref`, instead cache an anchor element and reuse it's href attributed

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Co-authored-by: Eoghan Murray <eoghan@getthere.ie>

.changeset/hungry-dodos-taste.md

@@ -0,0 +1,10 @@
+---
+'rrweb-snapshot': patch
+---
+
+Avoid recreating the same element every time, instead, we cache and we just update the element.
+
+Before: 779k ops/s
+After: 860k ops/s
+
+Benchmark: https://jsbench.me/ktlqztuf95/1