Don't recalculate length in every iteration #3

Job	Run time
Gather Environments	15s
Test cdata.js	48s
Build Enviornments (nodemcuv2)	1m 18s
Build Enviornments (esp8266_2m)	1m 8s
Build Enviornments (esp01_1m_full)	1m 4s
Build Enviornments (nodemcuv2_160)	1m 12s
Build Enviornments (esp8266_2m_160)	58s
Build Enviornments (esp01_1m_full_160)	1m 11s
Build Enviornments (esp32dev)	1m 24s
Build Enviornments (esp32_eth)	1m 9s
Build Enviornments (esp32dev_audioreactive)	1m 32s
Build Enviornments (lolin_s2_mini)	1m 53s
Build Enviornments (esp32c3dev)	1m 23s
Build Enviornments (esp32s3dev_8MB)	1m 48s
Build Enviornments (esp32s3dev_8MB_PSRAM_opi)	2m 16s
Build Enviornments (esp32_wrover)	1m 18s
Create Release	0s
	20m 37s

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