Fix bug that resulted in sporadic failed stream reassembly

The failure coincided with this error in the log:

msg="Stream parser reported error: read |0: file already closed"

The StdoutPipe docs explain the problem:
https://pkg.go.dev/os/exec?utm_source=godoc#Cmd.StdoutPipe

"Wait will close the pipe after seeing the command exit, so most callers
need not close the pipe themselves. It is thus incorrect to call Wait
before all reads from the pipe have completed. For the same reason, it
is incorrect to call Run when using StdoutPipe. See the example for
idiomatic usage."

My bug was that I Wait()ed for the stream process to end in a goroutine
while at the same time, I handed off the process's stdout to a parser to
build the stream data structures. Depending on timing, I might call
Wait() before the stream parser has finished reading the output - the
problem described above.

CHANGELOG.md

@@ -12,6 +12,7 @@
 
 ### Changed
 
+- Fixed a bug that resulted in stream reassembly sporadically failing and displaying a blank screen.
 - Termshark will now, by default, suppress errors from tshark. You can change this via the minibuffer
   `set suppress-tshark-errors` command.
 - Added a summary of standard error to the error dialogs displayed when a tshark process fails to run

pkg/streams/loader.go

@@ -205,9 +205,9 @@ func (c *Loader) loadStreamReassemblyAsync(pcapf string, proto string, idx int,
 
 	log.Infof("Started stream reassembly command %v with pid %d", c.streamCmd, c.streamCmd.Pid())
 
-	termshark.TrackedGo(func() {
+	defer func() {
 		termChan <- c.streamCmd.Wait()
-	}, Goroutinewg)
+	}()
 
 	pid = c.streamCmd.Pid()
 	procChan <- pid
@@ -219,7 +219,7 @@ func (c *Loader) loadStreamReassemblyAsync(pcapf string, proto string, idx int,
 	func() {
 		_, err := ParseReader("", streamOut, ops...)
 		if err != nil {
-			log.Infof("Stream parser reported error: %v", err)
+			log.Warnf("Stream parser reported error: %v", err)
 		}
 	}()