Added iconv extension to fix issues with newer symfony/polyfill-mbstr… #338

Job	Run time
matrix.name	0s
OK to pack?	-1s
build-linux-packages-arm64	0s
build-artifact-dev	0s
build-extra-packages	0s
build-linux-packages	0s
create-release	0s
upload-extra-packages	0s
upload-release	0s
upload-linux-packages	0s
deploy	0s
matrix.name	0s
update-manticoresearch-deps	0s
	-1s

Provide feedback