Align indentation where cabal check warns about it

[philderbeast]

Fixes the warning about inconsistent indentation in the package.

$ cabal check
...
Warning: elm.cabal:42:5: Inconsistent indentation. Indentation jumps at lines
42
...

Found when adding elm-compiler as an Updo example. I noticed the warning there:

$ cabal build all --enable-tests --enable-benchmarks
Warning: Unknown/unsupported 'ghc' version detected (Cabal 3.11.0.0 supports
'ghc' version < 9.8): /home/philderbeast/.ghcup/bin/ghc is version 9.8.1
Resolving dependencies...
Build profile: -w ghc-9.8.1 -O1
In order, the following will be built (use -v for more details):
 - elm-0.19.1 (exe:elm) (first run)
Warning: elm.cabal:42:5: Inconsistent indentation. Indentation jumps at lines
42
Configuring executable 'elm' for elm-0.19.1...
...

[github-actions]

Thanks for suggesting these code changes. To set expectations:

• Pull requests are reviewed in batches, so it can take some time to get a response.
• Smaller pull requests are easier to review. To fix nine typos, nine specific issues will always go faster than one big one. Learn why here.
• Reviewers may not know as much as you about certain situations, so add links to supporting evidence for important claims, especially regarding standards for CSS, HTTP, URI, etc.

Finally, please be patient with the core team. They are trying their best with limited resources.