Decorated class properties are now over-indented by ESLint

[ybnd]

Describe the bug
Apparently the indent rule in ESLint doesn't play well with decorated properties in TypeScript: they are indented with 4 spaces, e.g. here.

This doesn't cause any real problems but is a bit of an eyesore.

There is a potential workaround, but it disables indentation checks for all properties and won't be auto-fixable.
The ESLint rule itself is deprecated though (because it's a style rule and not a lint rule). They suggest to use this rule instead.

Expected behavior
Decorated properties should be indented with 2 spaces just like any other properties.

Related work
#2343

[ybnd]

There are a few other style rules used in DSpace Angular that have been deprecated in base ESLint & are now community-supported in @stylistic/eslint-plugins:

• indent
• comma-dangle
• object-curly-spacing
• eol-last
• brace-style
• keyword-spacing

Some of these include TypeScript-specific bugfixes now, but this doesn't address the over-indentation problem.

[ybnd]

Labeled as low priority since I applied the workaround in #2865 and it's unlikely that we'll have a better solution save for moving to Prettier.