new icon: dovecot (original, plain, line)

[weh]

Double check these details before you open a PR

• PR does not match another non-stale PR currently opened
• PR name matches the format new icon: Icon name (versions separated by comma). More details here
• PR's base is the develop branch.
• Your icons are inside a folder as seen here
• SVG matches the standards laid out here
• A new object is added in the devicon.json file as seen here

**This PR closes #2113 **

Link to prove your SVG is correct and up-to-date.

• Homepage: https://www.dovecot.org/
• Style guide: https://www.open-xchange.com/resources/brand-style-guide/dovecot-brand-style-guide/#logo

Some thoughts

i am not sure if it is ok to create a non-wordmark version.

Also there are two color variants for commercial and open source versions (See style guide).
I chose the open source color for original.

While editing the devicon.json i got doubts if a e-mail server is even matching our acceptance criteria.
So what do you think @Panquesito7 @Snailedlt @canaleal @lunatic-fox
Btw. if we decide to not add this, we should also close #2112

[canaleal]

I couldn't find a non-wordmark version of the logo on their website or style guide, so I suggest we stick with the word-mark version for now.

In terms of its acceptability, I'm somewhat undecided but leaning towards accepting it. Although the tool is essentially an email server, it's heavily utilized by IT professionals, administrators, and developers, which suggests it holds significance within our context.

Also excellent work, icons looks good. 👍

[github-actions]

Hi!

I'm the check-bot and we have some issues with your PR:

devicon.json is not sorted correctly.
Please make sure that your icon is added in the `devicon.json` file at the correct alphabetic position
as seen here: https://github.com/devicons/devicon/wiki/Updating-%60devicon.json%60

Check our CONTRIBUTING guide for more details regarding these errors.

Please address these issues. When you update this PR, I will check your SVGs again.

Thanks for your help,
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[github-actions]

Hi!

I'm the check-bot and we have some issues with your PR:

devicon.json is not sorted correctly.
Please make sure that your icon is added in the `devicon.json` file at the correct alphabetic position
as seen here: https://github.com/devicons/devicon/wiki/Updating-%60devicon.json%60

Check our CONTRIBUTING guide for more details regarding these errors.

Please address these issues. When you update this PR, I will check your SVGs again.

Thanks for your help,
SVG-Checker Bot 😄