Remove `msat` suffix from all clnrest responses

[ShahanaFarooqui]

All msat suffix should be removed from v23.05 onwards but clnrest responses still have the suffix.

For example amount_msat from listfunds, min_to_us_msat/max_to_us_msat/total_msat from listpeerchannels responses show values with msat.

{
	"outputs": [
		{
			"txid": "bbc6451f9c8e55af65c96a296122e6de6e71a5f52c6b741942a9d6b787884630",
			"output": 1,
			"amount_msat": "479704000msat",
			"scriptpubkey": "0014a3f056de0be075dcb3bde17af329abc629fdc06f",
			"address": "tb1q50c9dhstup6aevaau9a0x2dtcc5lmsr08elqnn",
			"status": "unconfirmed",
			"reserved": false
		}, ...
         ],
        "channels": [
		{
			"peer_id": "038863cf8ab91046230f561cd5b386cbff8309fa02e3f0c3ed161a3aeb64a643b9",
			"connected": false,
			"state": "ONCHAIN",
			"channel_id": "912c9f6a0bf542c83906fc701e3ddbe5568ba323bcaf414952de8913c03eaae1",
			"short_channel_id": "1859088x15x0",
			"our_amount_msat": "398018921msat",
			"amount_msat": "16776832000msat",
			"funding_txid": "e1aa3ec01389de524941afbc23a38b56e5db3d1e70fc0639c842f50b6a9f2c91",
			"funding_output": 0
		}, ...
       ]
}