[ecash-herald + token-server] Update typescript and docker build settings

Summary:
These apps are on a similar stack and seeing similar failures in CI.

I am not sure about the ecash-lib build related failure they are both now seeing in CI, but, since it happened after both added the "exclude: node_modules/" setting, I am removing this. Typescript does this by default, potentially it is interfering with other dependencies.

Add tsconfig.build.json so that we do not build the test files.

ecash-herald needs mock-chronik-client as this is used in scripts. Maybe we do not need to build scripts but they could be useful on the server.

Test Plan:
docker build -f ecash-herald.Dockerfile -t ecash-herald_local .
docker build -f token-server.Dockerfile -t token-server_local .

local builds pass, but I have not managed to repeat the failure currently seen in CI

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Subscribers: emack

Differential Revision: https://reviews.bitcoinabc.org/D17065