Inline parameter types for custom operators

There is no inlined parameter type for custom operators, as seen on a screenshot below

There are libraries that provide custom operators like `FSharpPlus` or `FParsec` which are notable F# libraries and this issue makes showing inlined parameter types inconsistent, which works only for basic pipe operator `|>`

Here's an example of how it works when there are mixed operators:

Tested on Rider, version 2020.2.3

Reproduce the inconsistent inline parameter-type display in Rider 2020.2.3 using custom operators from FSharpPlus or FParsec, including examples that mix custom operators with the basic pipe operator. Done means inline parameter types are shown consistently for custom operators as well as the pipe operator.

Written by the indexing model from the issue text.