change testthat parallel option to be false (#109)

* change parallel to be false

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Co-authored-by: Sam Schiano <125507018+Schiano-NOAA@users.noreply.github.com>

DESCRIPTION

@@ -57,7 +57,7 @@ Remotes:
     nmfs-ost/satf,
     r4ss/r4ss
 Config/testthat/edition: 3
-Config/testthat/parallel: true
+Config/testthat/parallel: false
 Encoding: UTF-8
 Language: en-US
 LazyData: true