Ensure 'interrupt' signal is fully sent before 'disconnect' (#292)

While this change does not wait for the target to be paused
it slightly slows down how long after interrupt is sent that
disconnect is sent.

See also #295

src/GDBTargetDebugSession.ts

@@ -535,9 +535,18 @@ export class GDBTargetDebugSession extends GDBDebugSession {
                 this.serialPort.close();
 
             if (this.targetType === 'remote') {
-                if (this.gdb.getAsyncMode() && this.isRunning)
-                    this.gdb.sendCommand('interrupt');
-                await this.gdb.sendCommand('disconnect');
+                if (this.gdb.getAsyncMode() && this.isRunning) {
+                    // See #295 - this use of "then" is to try to slightly delay the
+                    // call to disconnect. A proper solution that waits for the
+                    // interrupt to be successful is needed to avoid future
+                    // "Cannot execute this command while the target is running"
+                    // errors
+                    this.gdb
+                        .sendCommand('interrupt')
+                        .then(() => this.gdb.sendCommand('disconnect'));
+                } else {
+                    await this.gdb.sendCommand('disconnect');
+                }
             }
 
             await this.gdb.sendGDBExit();