[experiment] Support for JSX2

[developit]

Note: I don't necessarily think this is something we want to do. I just wanted to get an implementation up for folks investigating on the compilation side of things.

https://github.com/reactjs/rfcs/blob/createlement-rfc/text/0000-create-element-changes.md#jsx-transform-changes

[github-actions[bot]]

Size Change: +173 B (0%)

Total Size: 38.6 kB

Filename	Size	Change
dist/preact.js	3.75 kB	+48 B (1%)
dist/preact.min.js	3.75 kB	+48 B (1%)
dist/preact.module.js	3.76 kB	+35 B (0%)
dist/preact.umd.js	3.81 kB	+42 B (1%)

ℹ️ View Unchanged

Filename	Size	Change
compat/dist/compat.js	3 kB	0 B
compat/dist/compat.module.js	3.03 kB	0 B
compat/dist/compat.umd.js	3.05 kB	0 B
debug/dist/debug.js	3.08 kB	0 B
debug/dist/debug.module.js	3.07 kB	0 B
debug/dist/debug.umd.js	3.15 kB	0 B
devtools/dist/devtools.js	175 B	0 B
devtools/dist/devtools.module.js	185 B	0 B
devtools/dist/devtools.umd.js	252 B	0 B
hooks/dist/hooks.js	1.05 kB	0 B
hooks/dist/hooks.module.js	1.08 kB	0 B
hooks/dist/hooks.umd.js	1.13 kB	0 B
test-utils/dist/testUtils.js	390 B	0 B
test-utils/dist/testUtils.module.js	392 B	0 B
test-utils/dist/testUtils.umd.js	469 B	0 B

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