Apply suggestions from code review

Co-authored-by: Saleem Abdulrasool <[email protected]>

Author: tomerd

Sources/TSCBasic/Process.swift

@@ -416,10 +416,10 @@ public final class Process: ObjectIdentifierProtocol {
                 pendingLock.withLock {
                     if let stderr = pending {
                         self.stateLock.withLock {
-                            self?.state = .outputReady(stdout: .success(contents), stderr: .success(stderr))
+                            self.state = .outputReady(stdout: .success(contents.withUnsafeBytes { Array<UInt8>($0) }), stderr: .success(stderr))
                         }
                     } else {
-                        pending = contents
+                        pending = contents.withUnsafeBytes { Array<UInt8>($0) }
                     }
                 }
             }
@@ -429,10 +429,10 @@ public final class Process: ObjectIdentifierProtocol {
                 pendingLock.withLock {
                     if let stdout = pending {
                         self.stateLock.withLock {
-                            self?.state = .outputReady(stdout: .success(stdout), stderr: .success(contents))
+                            self.state = .outputReady(stdout: .success(stdout), stderr: .success(contents.withUnsafeBytes { Array<UInt8>($0) }))
                         }
                     } else {
-                        pending = contents
+                        pending = contents.withUnsafeBytes { Array<UInt8>($0) }
                     }
                 }
             }