Install composer.phar dependencies

[jrvosse]

See issue #1156
Added two lines to download composer.phar and install the dependencies.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!

0 Bugs
0 Vulnerabilities
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No Coverage information
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[codecov]

Codecov Report

Merging #1157 (0d83d18) into master (4a050f4) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #1157   +/-   ##
=========================================
  Coverage     67.97%   67.97%           
  Complexity     1584     1584           
=========================================
  Files            32       32           
  Lines          3888     3888           
=========================================
  Hits           2643     2643           
  Misses         1245     1245           

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[kinow]

Tested with the following steps:

• from master, docker-compose up --build (had deleted everything before, including the vendor folder)

• checked out this branch, deleted composer images/containers, then again docker-compose up --build

And still no vendor folder in the host, only in the container 👍

LGTM

Thanks for reporting it, and for the fix @jrvosse !

[osma]

I wanted to merge this but add a .dockerignore file in the same go. But since I don't have push access to the PR branch used here, I had to do it via an additional PR - #1162 . Since that PR is based on this PR, merging it will also merge the changes in this PR.