[Snyk] Upgrade lit-element from 2.4.0 to 2.5.1

[snyk-bot]

Snyk has created this PR to upgrade lit-element from 2.4.0 to 2.5.1.

:information_source: Keep your dependencies up-to-date. This makes it easier to fix existing vulnerabilities and to more quickly identify and fix newly disclosed vulnerabilities when they affect your project.

---

• The recommended version is 2 versions ahead of your current version.
• The recommended version was released a year ago, on 2021-05-06.

Release notes

Package name: lit-element

• 2.5.1 - 2021-05-06
• 2.5.0 - 2021-04-30
• 2.4.0 - 2020-08-19

from lit-element GitHub release notes

---

Note: You are seeing this because you or someone else with access to this repository has authorized Snyk to open upgrade PRs.

For more information:

🧐 View latest project report

🛠 Adjust upgrade PR settings

🔕 Ignore this dependency or unsubscribe from future upgrade PRs

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}