Fix 'Resource leak: <variable> is never closed' warnings (#2023)

Fix numerous places where using AutoCloseable objects without closing
them.

Changes:
- Upgrade JUnit from 5.10.0 to 5.11.4 (so `@AutoClose` can be used)
- Use `Files.copy()` to copy files
- Use try-with-resources when calling `Files.list()` or `Files.walk()`
- Use try-with-resources or `@AutoClose` to close `PhotonCamera` and
  `PhotonCameraSim` objects created by tests
- Update `SQLConfigTest` to use `@TempDir`

## Meta

Merge checklist:
- [x] Pull Request title is [short, imperative
summary](https://cbea.ms/git-commit/) of proposed changes
- [x] The description documents the _what_ and _why_
- [ ] If this PR changes behavior or adds a feature, user documentation
is updated
- [ ] If this PR touches photon-serde, all messages have been
regenerated and hashes have not changed unexpectedly
- [ ] If this PR touches configuration, this is backwards compatible
with settings back to v2024.3.1
- [ ] If this PR touches pipeline settings or anything related to data
exchange, the frontend typing is updated
- [ ] If this PR addresses a bug, a regression test for it is added

photon-lib/src/main/java/org/photonvision/simulation/VideoSimUtil.java

@@ -100,6 +100,14 @@ public class VideoSimUtil {
     /**
      * Gets the 10x10 (grayscale) image of a specific 36h11 AprilTag.
      *
+     * <p>WARNING: This creates a {@link RawFrame} instance but does not close it, which would result
+     * in a resource leak if the {@link Mat} is garbage-collected. Unfortunately, closing the {@code
+     * RawFrame} inside this function would delete the underlying data that backs the {@code
+     * ByteBuffer} that is passed to the {@code Mat} constructor (see comments on <a
+     * href="https://github.com/PhotonVision/photonvision/pull/2023">PR 2023</a> for details).
+     * Luckily, this method is private and is (as of Aug 2025) only used to populate the {@link
+     * #kTag36h11Images} static map at static-initialization time.
+     *
      * @param id The fiducial id of the desired tag
      */
     private static Mat get36h11TagImage(int id) {

photon-lib/src/main/java/org/photonvision/simulation/VisionSystemSim.java

@@ -122,6 +122,7 @@ public class VisionSystemSim {
      * @return If the camera was present and removed
      */
     public boolean removeCamera(PhotonCameraSim cameraSim) {
+        @SuppressWarnings("resource")
         boolean success = camSimMap.remove(cameraSim.getCamera().getName()) != null;
         camTrfMap.remove(cameraSim);
         return success;