When arc patch adds/removes binary files under PHP 8.1, it fails with several strlen(null) errors:
```
EXCEPTION: (RuntimeException) strlen(): Passing null to parameter #1 ($string) of type string is deprecated at [<arcanist>/src/error/PhutilErrorHandler.php:261]
arcanist(head=master, ref.master=8130241a11ac, custom=4)
#0 PhutilErrorHandler::handleError(integer, string, string, integer) called at [<arcanist>/src/parser/ArcanistBundle.php:765]
#1 ArcanistBundle::buildBinaryChange(ArcanistDiffChange, NULL) called at [<arcanist>/src/parser/ArcanistBundle.php:409]
#2 ArcanistBundle::toGitPatch() called at [<arcanist>/src/workflow/ArcanistPatchWorkflow.php:705]
#3 ArcanistPatchWorkflow::run() called at [<arcanist>/src/workflow/ArcanistPatchWorkflow.php:399]
#4 ArcanistPatchWorkflow::run() called at [<arcanist>/scripts/arcanist.php:427]
```
```
EXCEPTION: (RuntimeException) strlen(): Passing null to parameter #1 ($string) of type string is deprecated at [<arcanist>/src/error/PhutilErrorHandler.php:261]
arcanist(head=master, ref.master=df6c315ace5f)
#0 PhutilErrorHandler::handleError(integer, string, string, integer) called at [<arcanist>/src/parser/ArcanistBundle.php:765]
#1 ArcanistBundle::buildBinaryChange(ArcanistDiffChange, NULL) called at [<arcanist>/src/parser/ArcanistBundle.php:409]
#2 ArcanistBundle::toGitPatch() called at [<arcanist>/src/workflow/ArcanistPatchWorkflow.php:705]
#3 ArcanistPatchWorkflow::run() called at [<arcanist>/src/workflow/ArcanistPatchWorkflow.php:399]
#4 ArcanistPatchWorkflow::run() called at [<arcanist>/scripts/arcanist.php:427]
```