Hotfix: Downgrade curl version in PHP Images to 7.63.0

Bugfixes:
With the update of alpine in the PHP Images in Version v.0.20.0 curl/libcurl was also updated to version 7.64.0. Which unfortunately has a bug that in specific situations it is possible that it fills the error buffer even though there is no error happening. Depending on the implementation of the client code that uses libcurl, the client code can either correct realize that the request worked and the buffer should just be ignored. Or like in the situation of drupal-composer/drupal-scaffold the buffer is checked and an exception thrown even if the curl request worked correctly.
We have opened multiple issues to resolve this:

• curl: curl/curl#3629 which a PR is existing: curl/curl#3630
• drupal-scaffold drupal-composer/drupal-scaffold#102 which there is also a PR existing: drupal-composer/drupal-scaffold#103
  As this bug affects some of our customers and their projects cannot deploy anymore, we decided to hotfix release PHP Images which don't use the newest curl version 7.64.0 and instead ship with 7.63.0 where this problem does not exist yet.

As soon as there is a fixed curl version released and it is packaged via the alpine packaging system, we will update curl as well.