test: rename ExpectMatchContext to ExpectMatch (#25998)

Cleans the last few instances of ExpectMatch that didn't use the new `(ctx, ...)` variant, then deletes the deprecated method and renames `ExpectMatchContext` to drop the `Context` suffix.

agent/agent_test.go

@@ -673,7 +673,7 @@ func TestAgent_SessionTTYShell(t *testing.T) {
 			require.NoError(t, err)
 			_ = ptty.Peek(ctx, 1) // wait for the prompt
 			ptty.WriteLine("echo test")
-			ptty.ExpectMatch("test")
+			ptty.ExpectMatch(ctx, "test")
 			ptty.WriteLine("exit")
 			err = session.Wait()
 			require.NoError(t, err)

agent/agentssh/agentssh_test.go

@@ -203,7 +203,7 @@ func TestNewServer_CloseActiveConnections(t *testing.T) {
 				assert.NoError(t, err)
 
 				// Allow the session to settle (i.e. reach echo).
-				pty.ExpectMatchContext(ctx, "started")
+				pty.ExpectMatch(ctx, "started")
 				// Sleep a bit to ensure the sleep has started.
 				time.Sleep(testutil.IntervalMedium)