Panic when required argument was not defined

[srevinsaju]

0002 • [module.deploy]
panic: /tmp/togomak790217308/modules/deploy/variables.hcl:5,31-31: Missing required argument; The argument "key" is required, but no definition was found.

goroutine 32 [running]:
github.com/srevinsaju/togomak/v1/internal/blocks/data.Variables({0x1a9a1c0, 0xc0013114a0}, {0x1a93d50, 0xc0012e53f0})
        /home/srev/src/github.com/srevinsaju/togomak/internal/blocks/data/provider.go:62 +0x1fa
github.com/srevinsaju/togomak/v1/internal/ci.(*Data).Variables(0xc001334f78)
        /home/srev/src/github.com/srevinsaju/togomak/internal/ci/data_hcl.go:16 +0xff
github.com/srevinsaju/togomak/v1/internal/ci.GraphTopoSort(0xc000191b80, 0xc0010d9d00)
        /home/srev/src/github.com/srevinsaju/togomak/internal/ci/graph.go:94 +0x85b
github.com/srevinsaju/togomak/v1/internal/ci.(*Pipeline).Run(0xc000191b80?, 0xc000191b80)
        /home/srev/src/github.com/srevinsaju/togomak/internal/ci/pipeline_run.go:66 +0x565
github.com/srevinsaju/togomak/v1/internal/ci.(*Module).run(0xc001188fc0, 0xc000cf4c60, {0xc0000481e0, 0x4d}, 0xc00172ca50, {0xc00158b010, 0x2, 0x2})
        /home/srev/src/github.com/srevinsaju/togomak/internal/ci/module_run.go:238 +0x105a
github.com/srevinsaju/togomak/v1/internal/ci.(*Module).Run(0xc001188fc0, 0xc000cf4c60, {0xc00158b010, 0x2, 0x2})
        /home/srev/src/github.com/srevinsaju/togomak/internal/ci/module_run.go:82 +0xa56
github.com/srevinsaju/togomak/v1/internal/ci.BlockRunWithRetries(0x0?, {0xc000014d00, 0xd}, {0x1a9f640, 0xc001188fc0}, 0xc000cf8460, {0x1acd760?, 0xc000cc4800?}, {0xc00158b010, 0x2, ...})
        /home/srev/src/github.com/srevinsaju/togomak/internal/ci/run.go:16 +0x143
created by github.com/srevinsaju/togomak/v1/internal/ci.(*Pipeline).Run in goroutine 1
        /home/srev/src/github.com/srevinsaju/togomak/internal/ci/pipeline_run.go:127 +0xcf

we should be providing a good error message instead.