Merge pull request #95 from hideakitai/fix/build-error-for-unsubscribe #86

Job	Run time
Build Test (WiFiS3): renesas_uno:unor4wifi	1m 12s
Build Test (WiFiNINA): megaavr:uno2018	50s
Build Test (Ethernet): avr:uno	47s
Build Test (WiFiNINA): samd:mkrvidor4000	1m 13s
Build Test (ETH): esp32:esp32	2m 6s
Build Test (Ethernet): megaavr:uno2018	47s
Build Test (WiFiNINA): samd:mkrwifi1010	1m 16s
Build Test (ETH): esp32:esp32s3	1m 57s
Build Test (Ethernet): samd:mkrvidor4000	1m 10s
Build Test (EtherENC): megaavr:uno2018	52s
Build Test (WiFiNINA): samd:nano_33_iot	1m 7s
Build Test (ETH): esp32:esp32c3	1m 58s
Build Test (Ethernet): samd:mkrwifi1010	1m 14s
Build Test (EtherENC): samd:mkrwifi1010	1m 13s
Build Test (Ethernet): samd:mkr1000	1m 6s
Build Test (EtherENC): samd:mkr1000	1m 15s
Build Test (Ethernet): samd:nano_33_iot	1m 7s
Build Test (EtherENC): samd:nano_33_iot	1m 26s
Build Test (WiFi): esp8266:generic	1m 46s
Build Test (Ethernet): esp8266:generic	1m 8s
Build Test (EtherENC): esp8266:generic	1m 21s
Build Test (WiFi): esp32:esp32	1m 56s
Build Test (Ethernet): esp32:esp32	1m 20s
Build Test (EtherENC): esp32:esp32	1m 47s
Build Test (WiFi): esp32:esp32s3	1m 59s
Build Test (Ethernet): esp32:esp32s3	1m 23s
Build Test (EtherENC): esp32:esp32s3	1m 50s
Build Test (WiFi): esp32:esp32c3	1m 46s
Build Test (Ethernet): esp32:esp32c3	1m 21s
Build Test (EtherENC): esp32:esp32c3	1m 52s
Build Test (Ethernet): rp2040:rpipicow	1m 10s
Build Test (WiFi): rp2040:rpipicow	2m 15s
Build Test (EtherENC): rp2040:rpipicow	1m 19s
	46m 49s

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