docs: fix user creation example in Ubuntu-based Docker images (#1243) #1777

Job	Run time
prepare	12s
build (php-8-2-26-alpine, linux/amd64)	2m 53s
build (php-8-2-26-alpine, linux/386)	2m 59s
build (php-8-2-26-alpine, linux/arm/v7)	2m 58s
build (php-8-2-26-alpine, linux/arm64)	2m 58s
build (php-8-2-26-bookworm, linux/amd64)	3m 0s
build (php-8-2-26-bookworm, linux/386)	3m 1s
build (php-8-2-26-bookworm, linux/arm/v7)	2m 52s
build (php-8-2-26-bookworm, linux/arm64)	2m 56s
build (php-8-3-14-alpine, linux/amd64)	2m 51s
build (php-8-3-14-alpine, linux/386)	3m 0s
build (php-8-3-14-alpine, linux/arm/v7)	2m 58s
build (php-8-3-14-alpine, linux/arm64)	2m 59s
build (php-8-3-14-bookworm, linux/amd64)	2m 50s
build (php-8-3-14-bookworm, linux/386)	3m 1s
build (php-8-3-14-bookworm, linux/arm/v7)	2m 57s
build (php-8-3-14-bookworm, linux/arm64)	2m 50s
build (php-8-4-1-alpine, linux/amd64)	2m 58s
build (php-8-4-1-alpine, linux/386)	2m 58s
build (php-8-4-1-alpine, linux/arm/v7)	2m 56s
build (php-8-4-1-alpine, linux/arm64)	2m 57s
build (php-8-4-1-bookworm, linux/amd64)	2m 49s
build (php-8-4-1-bookworm, linux/386)	2m 50s
build (php-8-4-1-bookworm, linux/arm/v7)	2m 50s
build (php-8-4-1-bookworm, linux/arm64)	2m 56s
push	1s
	1h 10m 30s

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