Wrapped typeCheckErrors is causing pickling test error

[soronpo]

Issue #12656 is fixed by #13543 but surfaces a pickling issue of wrapped compiletime.testing.typeCheckErrors

Compiler version

Master branch

Minimized code

See issue #12656

Output

This output is from the pickling test comparison of run/i12656.scala

***** before-pickling.txt
                    <
                      <[ : scala.compiletime.testing.Error]:scala.Array[scala.compiletime.testing.Error]>@
                        tests\run\i12656.scala<108..108>
***** AFTER-PICKLING.TXT
                    <
                      <[ : scala.compiletime.testing.Error]:Seq[scala.compiletime.testing.Error]>@
                        tests\run\i12656.scala<108..108>
*****

Expectation

No difference in pickling.