fix(build) Revert main in concerto-core package

[jeromesimeon]

Signed-off-by: Jerome Simeon [email protected]

Changes

• Reverts part of chore: Migrate build tool #270 (the main for @accordproject/concerto-core) since min cannot be imported as is from other node projects

Context

When tried in markdown-transform, errors:

> @accordproject/[email protected] test /Users/jeromesimeon/git/accordproject/markdown-transform/packages/markdown-transform
> mocha

/Users/jeromesimeon/git/accordproject/markdown-transform/node_modules/mocha/node_modules/yargs/yargs.js:1163
      else throw err
           ^

ReferenceError: regeneratorRuntime is not defined
    at /Users/jeromesimeon/git/accordproject/markdown-transform/node_modules/@accordproject/concerto-core/dist/concerto.min.js:42:227469
    at /Users/jeromesimeon/git/accordproject/markdown-transform/node_modules/@accordproject/concerto-core/dist/concerto.min.js:42:228005
    at /Users/jeromesimeon/git/accordproject/markdown-transform/node_modules/@accordproject/concerto-core/dist/concerto.min.js:1:69
    at Object.<anonymous> (/Users/jeromesimeon/git/accordproject/markdown-transform/node_modules/@accordproject/concerto-core/dist/concerto.min.js:1:574)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)

Flags

• I don't know if that is a real fix or if chore: Migrate build tool #270 needs to be revisited