Restriction: Adding "weaving-death-place" flag

[RedstoneFuture]

Overview

This PR adds the "weaving-death-place" flag to prevent spawning of cobwebs on death by the Weaving status effect.

Fixes #4517

Description

• adding new flag "weaving-death-place" (default false)
• adding checks in the EntityChangeBlockEvent

The default value is “false”, because in my opinion it is rarely intended that the death of an entity on its own plot (including its own death) should spawn cobwebs on the plot (or other plots or the plot path). Especially because the status effect can be maintained by external factors (minecraft:lingering_potion). That makes the behavior so special that I wanted to handle it in a new custom flag rather than using an existing flag.

Only since 1.21.x are there status effects that spawn or change blocks on death. I will expand the restriction of wind-charge in another PR to improve the restriction for the new 1.21 features / behaviors.

### Submitter Checklist
- [X] Make sure you are opening from a topic branch (**/feature/fix/docs/ branch** (right side)) and not your main branch.
- [X] Ensure that the pull request title represents the desired changelog entry.
- [X] New public fields and methods are annotated with `@since TODO`.
- [X] I read and followed the [contribution guidelines](https://github.com/IntellectualSites/.github/blob/main/CONTRIBUTING.md).

[SirYwell]

Looks good. Please also open a PR to add the flag to the documentation (https://github.com/IntellectualSites/documentation/blob/main/plotsquared/plot-flags.md). Thanks!

[RedstoneFuture]

PS-Flag documentation update: IntellectualSites/documentation#133

Changes addressed