Fix `addConfigFileContent` regression #367

Job	Run time
build / linux-gcc-14-amd64 (Nim devel)	3m 38s
build / linux-amd64 (Nim version-2-0)	14s
build / windows-amd64 (Nim devel)	5m 17s
build / linux-gcc-14-amd64 (Nim version-1-6)	1m 56s
build / windows-amd64 (Nim version-1-6)	35s
build / linux-i386 (Nim version-1-6)	2m 28s
build / macos-amd64 (Nim version-1-6)	3m 10s
build / linux-amd64 (Nim version-2-2)	3m 0s
build / linux-gcc-14-amd64 (Nim version-2-0)	3m 14s
build / linux-i386 (Nim devel)	4m 33s
build / linux-amd64 (Nim version-1-6)	1m 59s
build / linux-amd64 (Nim devel)	3m 50s
build / linux-gcc-14-amd64 (Nim version-2-2)	3m 12s
build / windows-amd64 (Nim version-2-0)	5m 22s
build / macos-amd64 (Nim version-2-2)	4m 28s
build / linux-i386 (Nim version-2-2)	3m 59s
build / windows-amd64 (Nim version-2-2)	5m 16s
build / macos-arm64 (Nim version-2-2)	5m 17s
build / macos-amd64 (Nim version-2-0)	5m 8s
build / macos-arm64 (Nim devel)	5m 21s
build / linux-i386 (Nim version-2-0)	3m 48s
build / macos-arm64 (Nim version-1-6)	2m 1s
build / macos-arm64 (Nim version-2-0)	5m 21s
build / macos-amd64 (Nim devel)	5m 4s
	1h 28m 11s

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