gopls/internal/telemetry: don't schedule the next upload

The telemetry upload package implementation queries UploadConfig
only once and reuses it throughout the process lifetime. So, periodic
upload doesn't work. Assume users frequently restart gopls or eventually
we will move the upload logic to go which is frequently invoked, and
run upload only once at the start up.

It's still better to clean up the cached upload config object
after upload is complete.

Fixes golang/go#62405

Change-Id: I39395cf876d9f0e570a71da5284420f570dcdc6b
Reviewed-on: https://go-review.googlesource.com/c/tools/+/524819
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
Reviewed-by: Peter Weinberger <pjw@google.com>

gopls/internal/telemetry/telemetry.go

@@ -9,7 +9,6 @@ package telemetry
 
 import (
 	"fmt"
-	"time"
 
 	"golang.org/x/telemetry/counter"
 	"golang.org/x/telemetry/upload"
@@ -19,14 +18,8 @@ import (
 // Start starts telemetry instrumentation.
 func Start() {
 	counter.Open()
-	go packAndUpload()
-}
-
-func packAndUpload() {
-	start := time.Now()
-	upload.Run(nil)
-	elapsed := time.Since(start)
-	time.AfterFunc(24*time.Hour-elapsed, packAndUpload)
+	// upload only once at startup, hoping that users restart gopls often.
+	go upload.Run(nil)
 }
 
 // RecordClientInfo records gopls client info.