fix: headers are optional

[edewit]

for references see: https://github.com/vert-x3/vertx-web/blob/14d183b9e79f568e69fe7c5b683e61a833e6829f/vertx-web/src/client/vertx-eventbus.js#L282-L284

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[typescript-bot]

👋 Hi there! I’ve run some quick measurements against master and your PR. These metrics should help the humans reviewing this PR gauge whether it might negatively affect compile times or editor responsiveness for users who install these typings.

Let’s review the numbers, shall we?

Comparison details 📊

	master	#44263	diff
Batch compilation
Memory usage (MiB)	36.1	36.1	+0.1%
Type count	2145	2148	0%
Assignability cache size	110	110	0%
Language service
Samples taken	3	3	0%
Identifiers in tests	3	3	0%
getCompletionsAtPosition
Mean duration (ms)	95.4	90.9	-4.7%
Mean CV	31.0%	35.9%
Worst duration (ms)	104.6	95.6	-8.6%
Worst identifier	EventBus	EventBus
getQuickInfoAtPosition
Mean duration (ms)	76.0	79.0	+3.9%
Mean CV	25.0%	17.5%	-30.0%
Worst duration (ms)	79.7	86.3	+8.2%
Worst identifier	EventBus	EventBus

It looks like nothing changed too much. I won’t post performance data again unless it gets worse.

[typescript-bot]

@edewit Thank you for submitting this PR! I see this is your first time submitting to DefinitelyTyped 👋 - keep an eye on this comment as I'll be updating it with information as things progress.

This PR doesn't modify any tests, so it's hard to know what's being fixed, and your changes might regress in the future. Have you considered adding tests to cover the change you're making? Including tests allows this PR to be merged by yourself and the owners of this module. This can potentially save days of time for you.

Code Reviews

This PR can be merged once it's reviewed by a DT maintainer.

Status

• ✅ No merge conflicts
• ✅ Continuous integration tests have passed
• ❌ Only a DT maintainer can merge changes without tests

Once every item on this list is checked, I'll ask you for permission to merge and publish the changes.

---

Diagnostic Information: What the bot saw about this PR

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[typescript-bot]

🔔 @oddeirik - please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.