build: remove experimental label for nrf54l10

[ktaborowski]

This reverts commit 5b5cc72.

CI parameters

Github_actions:
  #(branch, hash, pull/XXX/head)
  NRF_revision: main

  # Do not change after creating PR
  Create_NRF_PR: false
Jenkins:
  test-sdk-sidewalk: master

Description

JIRA ticket:

Self review

• There is no commented code.
• There are no TODO/FIXME comments without associated issue ticket.
• Commits are properly organized.
• Change has been tested.
• Tests were updated (if applicable).

[github-actions]

Sample		diff	used	total
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.demo.ble_only	RAM	0 B	105.82 KB	0 B
	ROM	112 B	328.57 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.dut	RAM	0 B	144.62 KB	0 B
	ROM	112 B	473.01 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.dut.ble_only	RAM	0 B	129.51 KB	0 B
	ROM	112 B	394.73 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.dut.no_secure	RAM	0 B	144.62 KB	0 B
	ROM	112 B	470.31 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.hello	RAM	0 B	122.31 KB	0 B
	ROM	112 B	421.62 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.hello.ble_only	RAM	0 B	95.87 KB	0 B
	ROM	112 B	326.87 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.hello.ble_only.release	RAM	0 B	91.23 KB	0 B
	ROM	112 B	256.38 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.hello.release	RAM	0 B	106.29 KB	0 B
	ROM	112 B	332.26 KB	0 B
nrf54l15dk/nrf54l15/cpuapp/ns:sample.sidewalk.demo	RAM	0 B	120.87 KB	0 B
	ROM	112 B	406.31 KB	0 B