Twig deprecations

[prudloff-insite]

Describe the bug
satis build triggers these deprecations:

Deprecation Notice: Since twig/twig 3.12: Character "D" should not be escaped; the "\" character is ignored in Twig 3 but will not be in Twig 4. Please remove the extra "\" character at position 2 in "index.html.twig" at line 36. in /var/www/vendor/symfony/deprecation-contracts/function.php:25
Deprecation Notice: Since twig/twig 3.12: Character "D" should not be escaped; the "\" character is ignored in Twig 3 but will not be in Twig 4. Please remove the extra "\" character at position 2 in "index.html.twig" at line 37. in /var/www/vendor/symfony/deprecation-contracts/function.php:25
Deprecation Notice: Since twig/twig 3.12: Character "/" should not be escaped; the "\" character is ignored in Twig 3 but will not be in Twig 4. Please remove the extra "\" character at position 11 in "package.html.twig" at line 100. in /var/www/vendor/symfony/deprecation-contracts/function.php:25
Deprecation Notice: Since twig/twig 3.12: Character "/" should not be escaped; the "\" character is ignored in Twig 3 but will not be in Twig 4. Please remove the extra "\" character at position 13 in "package.html.twig" at line 100. in /var/www/vendor/symfony/deprecation-contracts/function.php:25

To Reproduce
Call satis build with Twig 3.16.0.

Expected behavior
No deprecation.

Additional context
I think it comes from these anti-slashes:

• satis/views/index.html.twig

  Line 36 in 79d28d7

  <span class="badge bg-light text-dark m-1" title="{{ "now"|date(constant('\DateTime::COOKIE')) }}">

• satis/views/package.html.twig

  Line 100 in 79d28d7

  {%- elseif version.sourceUrl matches '#^https?:\/\/#' -%}

I suppose we need to do something like this:

{{ "now"|date(constant('\\DateTime::COOKIE')) }}

[alcohol]

I think #947 resolved this?