Replacing String concatenation, now StringBuilder is being used

[sergioescala]

No description provided.

[codecov-io]

Codecov Report

Merging #591 into master will not change coverage.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master     #591   +/-   ##
=========================================
  Coverage     98.09%   98.09%           
  Complexity      350      350           
=========================================
  Files             4        4           
  Lines          4096     4096           
  Branches       1005     1005           
=========================================
  Hits           4018     4018           
  Misses           23       23           
  Partials         55       55

Impacted Files	Coverage Δ	Complexity Δ
src/main/java/picocli/AutoComplete.java	96.68% <100%> (ø)	106 <0> (ø)	⬇️

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[remkop]

Looks good. I’ve started the release for picocli-3.9.0; I’ll merge this when the release is done. Thanks for the PR!

[remkop]

Merged.
I’ll update the release notes (for the next release) later.
Thanks for the pull request!

[sergioescala]

Thanks to you @remkop for merging my changes!