Add missing space in hydration mismatch message

[sirreal]

The message reads something like this:

Expected a DOM node of type p but found templateas available DOM-node(s), this is caused by the SSR'd HTML containing different DOM-nodes compared to the hydrated one.

It should read

Expected a DOM node of type p but found template as available DOM-node(s), this is caused by the SSR'd HTML containing different DOM-nodes compared to the hydrated one.

"templateas" should be "template as"

-Expected a DOM node of type p but found templateas available DOM-node(s), this is caused by the SSR'd HTML containing different DOM-nodes compared to the hydrated one.
+Expected a DOM node of type p but found template as available DOM-node(s), this is caused by the SSR'd HTML containing different DOM-nodes compared to the hydrated one.

[coveralls]

coverage: 99.617%. remained the same
when pulling d2904b9 on sirreal:patch-1
into 5c9625a on preactjs:main.