RemoveUnusedBinding offers to remove unused parameters but doesn't remove them

**Is your feature request related to a problem? Please describe.**

I think [this reported issue/feature gap](https://github.com/fsharp/FsAutoComplete/issues/811) in FSAC is reproducible in the VS tooling as well.

For the code:

```fsharp
let inc i =
2
```

with `--warnon:1182` enabled, there will be a diagnostic issued for the parameter `i`, but the [current codefix](https://github.com/dotnet/fsharp/blob/48e06db01c48fc01e382d7db5304ffb79725eef4/vsintegration/src/FSharp.Editor/CodeFix/RemoveUnusedBinding.fs) will not handle this scenario.

**Describe the solution you'd like**

I think a [small change](https://github.com/fsharp/FsAutoComplete/pull/812/files#diff-6e83d7b88f34d7f59884a533720e78dc4ecc5bc41f566309881b238e567abe3eR19-R66) to the [TryRangeOfBindingWithHeadPatternWithPos](https://github.com/dotnet/fsharp/blob/3a3fac2080e9b99eb30a97bd789ad456075a1aaf/vsintegration/src/FSharp.Editor/Common/FSharpCodeAnalysisExtensions.fs#L9) member could be made very similarly to what I've done in [this PR](https://github.com/fsharp/FsAutoComplete/pull/812), and the range that is derived from this member could be tagged as coming from a pattern or a binding.

Then, later in the codefix that result would be inspected to [walk the text in slightly different ways for patterns and bindings](https://github.com/fsharp/FsAutoComplete/pull/812/files#diff-6e83d7b88f34d7f59884a533720e78dc4ecc5bc41f566309881b238e567abe3eR78-R107), so that both kinds of triggering entities for this diagnostic could be handled.

**Describe alternatives you've considered**

Not doing this work, so that only nested bindings are removable.