fix: Use force-cache when fetching debug IDs

[timfish]

When fetching JavaScript source files to get their debug IDs, we leave the cache setting as default which means:

• default — The browser looks for a matching request in its HTTP cache.
  • If there is a match and it is fresh, it will be returned from the cache.
  • If there is a match but it is stale, the browser will make a conditional request to the remote server. If the server indicates that the resource has not changed, it will be returned from the cache. Otherwise the resource will be downloaded from the server and the cache will be updated.
  • If there is no match, the browser will make a normal request, and will update the cache with the downloaded resource.

In the case of fetching debug IDs, we are not bothered about the cache match being fresh or stale. Regardless of the staleness, the source file in the cache is much more likely to be the code that is currently executing.

• force-cache — The browser looks for a matching request in its HTTP cache.
  • If there is a match, fresh or stale, it will be returned from the cache.
  • If there is no match, the browser will make a normal request, and will update the cache with the downloaded resource.

Using force-cache can result in less conditional requests checking if the source has changed.

Of course, Sentrys JavaScript assets might be so heavily cached that this makes little to no difference!

[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀