fix: container build & shell make targets

Signed-off-by: Vladislav Doster <mvdoster@gmail.com>

Makefile

@@ -1,7 +1,6 @@
 .EXPORT_ALL_VARIABLES:
 
 ZSH := $(shell command -v zsh 2> /dev/null)
-SHELL = $(ZSH)
 SRC := share/{'git-process-output','rpm2cpio'}.zsh zinit{'','-additional','-autoload','-install','-side'}.zsh
 DOC_SRC := $(foreach wrd,$(SRC),../$(wrd))
 HAS_TTY := $(shell zsh -c "(( $${+GITHUB_ACTIONS} )) && echo '' || echo '--tty'")