[v13] fix: Ignore staticcheck false positive on darwin

[codingllama]

Backport #28038 to branch/v13

staticcheck is too clever for its own good and thinks that
HandleTPMActivateCredential only ever returns non-nil. While this is true for
darwin, it ain't true in other platforms.

Before the fix (on darwin):

$ golangci-lint run --fast ./tool/tsh/common ./lib/devicetrust/native
tool/tsh/common/device.go:172:17: SA4023: this comparison is always true (staticcheck)
	if cf.Debug && err != nil {
	               ^
tool/tsh/common/device.go:169:2: SA4023(related information): the lhs of the comparison is the 1st return value of this function call (staticcheck)
	err := dtnative.HandleTPMActivateCredential(
	^
lib/devicetrust/native/api.go:60:1: SA4023(related information): github.com/gravitational/teleport/lib/devicetrust/native.HandleTPMActivateCredential never returns a nil interface value (staticcheck)
func HandleTPMActivateCredential(encryptedCredential string, encryptedCredentialSecret string) error {
^

[codingllama]

Friendly ping @zmb3 ?