fix(core): 🐛 Preserve meaningful whitespace

[TzviPM]

Fixes #1218

Description

Some code generators were joining blocks with newlines (\n), which, when run through the dedent helper, would then trim any trailing whitespace. This ended up causing problems with significant whitespace in some scenarios.

This PR simply changes the join operation to use the empty string. The parser for mitosis already preserves the significant whitespace, so this makes the output components more closely resemble their mitosis source code. Prettier can still be used to format the output code, which will use a syntax tree that preserves meaningful whitespace while avoiding excessively long line lengths and adding stylistic line breaks.

The main focus for review should be:

1. Ensure that the large changes to snapshots are correct.
2. Considering that many generators have the same structure in terms of a componentToX function that calls a blockToX function recursively and joins children together, would it make sense to have a helper method for the join operation so that this type of change can be made more accurately across generators?

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Name	Status	Preview	Comments	Updated (UTC)
mitosis-fiddle	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jul 8, 2023 5:59pm

[TzviPM]

This seems unrelated to my changes. It must have been regenerated when I updated the snapshots. Please confirm if this is correct, or if I should revert this file

[samijaber]

Are you on the latest main? This change shouldn't happen.

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✅ Successfully ran 4 targets

• nx build @builder.io/mitosis-fiddle
• nx run-many --skip-nx-cache --target build --parallel 4 --exclude */e2e-alpine,*/e2e-angular,@builder.io/mitosis-fiddle,@builder.io/talk-*,@builder.io/example-apps
• nx build @builder.io/eslint-plugin-mitosis
• nx build @builder.io/mitosis

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[samijaber]

You also need to run yarn run fmt to lint your PR

[samijaber]

Awesome PR, thanks for raising it! I believe this also helps us close #310, which was waiting on React/Solid generator to stop creating new lines for each text block. :)