added footprint for Sensirion SHT4x humidity sensor

Required Settings:

Please configure your personal fork of the KiCad project with the following settings:

• 1. Settings->General->Visibility->Pipelines should be enabled and set to "Everyone with access".
• 2. Settings->CI/CD->General Pipelines timeout should be set to >3h .

Configure the merge request as follows:

• 1. The "Allow commits from members who can merge to the target branch." option check box at the bottom of your merge request must be checked.
  • This can later be enabled via the edit button found at the top right (in case you forgot to do it when creating the merge request).

#General Guidelines:

• 1. Do not submit a merge request against the master branch of your fork. Always create a new branch for merge requests.
• 2. If your script changes create footprints then provide a URL to a datasheet for the footprint(s) you are contributing.

https://sensirion.com/media/documents/33FD6951/624C4357/Datasheet_SHT4x.pdf

• 3. Provide a link to the merge request on the footprint repo that adds the result of your script.
• 5. Check the output of the automated check scripts - fix any errors as required.

added footprint for Sensirion SHT4x humidity sensor

kicad-symbols!3674 (merged)