Formatter: Preserve inline whitespace in ERB branches

[marcoroth]

This pull request fixes the formatter silently deleting whitespace between text and ERB tags when that text sits inside an else, elsif, when, in, rescue or ensure branch.

Found while adopting the formatter on RubyEvents in rubyevents/rubyevents#2013

Minimal reproduction:

<span><% if a %>A<% else %>B <%= d %><% end %></span>

Before

<span><% if a %>A<% else %>B<%= d %><% end %></span>

After

<span><% if a %>A<% else %>B <%= d %><% end %></span>

No nesting is required, any text node touching an ERB tag inside a branch loses its edge whitespace. The same input in the if branch was always formatted correctly, which is what made this hard to spot.

[github-actions]

🌿 Interactive Playground and Documentation Preview

A preview deployment has been built for this pull request. Try out the changes live in the interactive playground:

• Playground Preview
• Documentation Preview
• Website Preview

---

_{🌱 Grown from commit d970900}

---

✅ Preview deployment has been cleaned up.

[pkg-pr-new]

npx https://pkg.pr.new/@herb-tools/formatter@2015

npx https://pkg.pr.new/@herb-tools/language-server@2015

npx https://pkg.pr.new/@herb-tools/linter@2015

commit: d970900