fix(responsive): #MZI-12 fix mail reading on small screen

[Alex-Delaveau]

Describe your changes

Fixed an issue where reading emails with multiple responses on a small screen was uncomfortable.

Checklist tests

Respond multiple times to an email and check if it's readable on a small screen.

Issue ticket number and link

MZI-12

Checklist before requesting a review (magic string, indentation, comment/documentation...)

• I have detailed the tests to do in my feature/fix in order to prevent consequents regressions (must specify in Checklist tests)
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (API Doc etc...) - (must specify in Description for target version)
• If it is a consequent feature, I have added thorough tests.
• I have added tests that prove my fix is effective or that my feature works
• Any dependent changes have been added to this project (must specify in Description)