Fix "bash: line 1: @echo: command not found"

[zioproto]

The @ symbol before the echo is wrong here, and causes the following error:

% docker run --rm -v $(pwd):/src -w /src mcr.microsoft.com/azterraform:latest make pre-commit
curl -H 'Cache-Control: no-cache, no-store' -sSL ""https://raw.githubusercontent.com/Azure/tfmod-scaffold/main/scripts"/tffmt.sh" | bash
bash: line 1: @echo: command not found

I think it is a cut and paste error from here:

tfmod-scaffold/avmmakefile

Line 14 in aa74630

@echo "==> Fixing source code with gofmt..."

But in the Makefile syntax the @ symbol is correct

[lonegunmanb]

Thanks @zioproto for this one! Good catch!