Use corepack instead of npm for yarn install

[ari-party]

trafficstars

Dockerfile build was failing

 => ERROR [builder 11/14] RUN npm install -g yarn                                                                                                                                                                                                                                                                     0.2s 
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 > [builder 11/14] RUN npm install -g yarn:
0.190 /bin/sh: 1: npm: not found
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With fix:

 => [builder 11/15] RUN corepack enable                                                                                                                                                                                                                                                                               0.4s 
 => [builder 12/15] RUN corepack prepare [email protected] --activate                                                                                                                                                                                                                                                      0.7s 
 => [builder 13/15] RUN cd embedg-site && yarn install && yarn build && cd ..                                                                                                                                                                                                                                         4.9s
 => => # yarn install v1.22.22
 => => # [1/5] Validating package.json...