fix(push): fixes push notifications not showing (#100)

[btaens]

📋 Description

Fixes push notifications not showing on any desktops by checking whether target has image_url when retrieving iconChat, avoiding an exception thrown as described in #100.

🗂 Type

• 🍾 Feature
• 🚨 Bugfix
• 📒 Documentation
• 👷 Internals

🔥 Severity

• 💎 Non-Breaking Changes
• 💔 Breaking Changes

🖥 Platforms

• 🍏 macOS
• 💾 Windows
• 🐧 Linux

🛃 Tests

• My changes have been tested manually.
• My changes are covered by automated testing methods.

👨‍🎓 Miscellaneous

• My changes follow the style guide.
• My changes require updates to the documentation.

[sidneys]

@btaens Thank you, this will be in the next release as well.