yarn synthetic-chain build relies on tsx which may not be installed

[ivanlei]

Description

When attempting to yarn synthetic-chain build in agoric-sdk/a3p-integration I ran into an issue where tsx was not installed:

$ yarn synthetic-chain build
$ /Users/ivanleichtling/source/agoric/agoric-sdk/a3p-integration/node_modules/.bin/synthetic-chain build
env: tsx: No such file or directory
error Command failed with exit code 127.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
error Command failed with exit code 127.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
error Command failed with exit code 127.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

The issue seems to stem from the removal of tsx and a dependency in package.json in #102 while not fully removing the production dependency on tsx

Impact

This breaks local builds of agoric-sdk when tsx is not globally installed.

Work Around

$ npm install --global 'tsx@^3.14.0' 

[ivanlei]

Note CI does not catch this which suggests CI globally installs tsx.

[mhofman]

I'm not sure how I didn't catch this. tsx is not installed on my machine, but synthetic-chain does start correctly.

CI does still install tsx globally I believe.