DEVELOPERS: remove Nicolas Tran

Nicolas Tran is apparently no longer at Smile:

The response from the remote server was:
450 4.1.1 <nicolas.tran@smile.fr>: Recipient address rejected: User unknown in virtual mailbox table

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

DEVELOPERS

@@ -2221,10 +2221,6 @@ N:	Nicolas Serafini <nicolas.serafini@ik.me>
 F:	package/exiv2/
 F:	package/ofono/
 
-N:	Nicolas Tran <nicolas.tran@smile.fr>
-F:	package/dust/
-F:	package/hyperfine/
-
 N:	Niklas Cassel <niklas.cassel@wdc.com>
 F:	configs/qemu_riscv64_nommu_virt_defconfig