Fix array signals when used as jsx

[JoviDeCroock]

Fixes #665

We forgot that an Array can't be optimised rendered, this is considered not a valid element but also isn't text. We used to catch this with nodeType checks https://github.com/preactjs/signals/blob/%40preact/signals%401.3.2/packages/preact/src/index.ts#L97

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🦋 Changeset detected

Latest commit: 340d736

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@preact/signals	Patch

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[github-actions]

Size Change: +274 B (+0.33%)

Total Size: 83.6 kB

Filename	Size	Change
docs/dist/assets/bench.********.js	1.59 kB	+2 B (+0.13%)
docs/dist/assets/index.********.js	1.07 kB	+239 B (+28.59%)	🚨
docs/dist/assets/signals.module.********.js	2.23 kB	+11 B (+0.5%)
docs/dist/demos-********.js	3.44 kB	+1 B (+0.03%)
packages/preact/dist/signals.js	1.55 kB	+13 B (+0.84%)
packages/preact/dist/signals.mjs	1.52 kB	+8 B (+0.53%)

ℹ️ View Unchanged

Filename	Size
docs/dist/assets/client.********.js	46.2 kB
docs/dist/assets/jsxRuntime.module.********.js	284 B
docs/dist/assets/preact.module.********.js	4.03 kB
docs/dist/assets/signals-core.module.********.js	1.41 kB
docs/dist/assets/style.********.js	21 B
docs/dist/assets/style.********.css	1.24 kB
docs/dist/basic-********.js	243 B
docs/dist/nesting-********.js	1.13 kB
docs/dist/react-********.js	242 B
packages/core/dist/signals-core.js	1.45 kB
packages/core/dist/signals-core.mjs	1.47 kB
packages/react-transform/dist/signals-*********.js	4.93 kB
packages/react-transform/dist/signals-transform.mjs	4.16 kB
packages/react-transform/dist/signals-transform.umd.js	5.04 kB
packages/react/dist/signals.js	188 B
packages/react/dist/signals.mjs	150 B

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[marvinhagemeister]

Good catch!