extra line after comments breaks pipelines

Describe the bug

Nufmt adds a newline after comments, potentially breaking pipelines.

Script or statement

$env.config = $env.config
# | upsert edit_mode vi
| upsert show_banner false

Actual behavior/output

$env.config = $env.config
# | upsert edit_mode vi

| upsert show_banner false

The newline added after the comment breaks the pipeline:

Error: nu::parser::input_type_mismatch

  × Command does not support nothing input.
   ╭─[/home/pheenty/a.nu:4:3]
 3 │
 4 │ | upsert show_banner false
   ·   ───┬──
   ·      ╰── command doesn't support nothing input
   ╰────

Expected behavior/output

$env.config = $env.config
# | upsert edit_mode vi
| upsert show_banner false

(nothing should change)

Environment

❯ $nu.os-info
╭────────────────┬───────────────╮
│ name           │ linux         │
│ arch           │ x86_64        │
│ family         │ unix          │
│ kernel_version │ 7.1.8-arch1-3 │
╰────────────────┴───────────────╯
❯ nufmt --version
nufmt 0.1.4

Run nufmt 0.1.4 on the supplied Nushell script and compare its output with the expected example. Trace the formatter entry point that handles comments and pipeline lines, then add or update coverage for this reproduction. Done means formatting leaves the comment and following pipeline command adjacent, without introducing a blank line.