internal/crashmonitor: use the built-in min/max function

Starting from Go 1.21, the min/max functions are built-in.

Therefore, we can remove the custom functions with the same name.

Change-Id: I8548b4ead6c536c8da492c6fc3fb8fb71ce3c2e6
Reviewed-on: https://go-review.googlesource.com/c/telemetry/+/707515
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Sean Liao <sean@liao.dev>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Sean Liao <sean@liao.dev>
Reviewed-by: Peter Weinberger <pjw@google.com>

internal/crashmonitor/monitor.go

diff --git a/internal/crashmonitor/monitor.go b/internal/crashmonitor/monitor.go
index 53966ad..ac22f68 100644
--- a/internal/crashmonitor/monitor.go
+++ b/internal/crashmonitor/monitor.go
@@ -326,11 +326,3 @@
 	}
 	return pcs, nil
 }
-
-func min(x, y int) int {
-	if x < y {
-		return x
-	} else {
-		return y
-	}
-}