Adds a Map Changelog Entry Category (tgstation#87034)

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## About The Pull Request

This should hopefully cut down on mappers using the add:/fix:/del: tag
I've talked to the maptainers about this and they seem to not be
concerned about gbp in their own system, so we should be trying to push
mappers away from using add/remove/(maybe? closing issues is cool) fix
tags and such to avoid overlap.

I've intentionally not linked this to a label due to the Map Edit label
autodetecting anyway. Should be directed only at players.

This does mean less label resolution on mapping prs, not sure how I feel
about that but I didn't want to duplicate the old image
add/remove/change labels.

Requesting wider input on this and also pinging to notify.
@tgstation/commit-access @tgstation/maptainers 

## Changelog

<!-- If your PR modifies aspects of the game that can be concretely
observed by players or admins you should add a changelog. If your change
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mark your PRs to prevent unnecessary GBP loss. You can read up on GBP
and its effects on PRs in the tgstation guides for contributors. Please
note that maintainers freely reserve the right to remove and add tags
should they deem it appropriate. You can attempt to finagle the system
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:cl:
map: added a map specific changelog entry
/:cl:

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icon ingame) and delete the unneeded ones. Despite some of the tags,
changelogs should generally represent how a player might be affected by
the changes rather than a summary of the PR's contents. -->

.github/PULL_REQUEST_TEMPLATE.md

@@ -22,6 +22,7 @@ balance: rebalanced something
 fix: fixed a few things
 sound: added/modified/removed audio or sound effects
 image: added/modified/removed some icons or images
+map: added/modified/removed map content
 spellcheck: fixed a few typos
 code: changed some code
 refactor: refactored some code

tgui/packages/tgui/interfaces/Changelog.jsx

@@ -37,6 +37,7 @@ const icons = {
   soundadd: { icon: 'tg-sound-plus', color: 'green' },
   sounddel: { icon: 'tg-sound-minus', color: 'red' },
   spellcheck: { icon: 'spell-check', color: 'green' },
+  map: { icon: 'map', color: 'green' },
   tgs: { icon: 'toolbox', color: 'purple' },
   tweak: { icon: 'wrench', color: 'green' },
   unknown: { icon: 'info-circle', color: 'label' },

tools/pull_request_hooks/changelogConfig.js

@@ -53,6 +53,13 @@ export const CHANGELOG_ENTRIES = [
 		},
 	],
 
+	[
+		["map"],
+		{
+			placeholders: ["added/modified/removed map content"],
+		},
+	],
+
 	[
 		["spellcheck", "typo"],
 		{