WPILib 2026.2.1 (#2306)

## Description

Find-and-replace 2026.1.1 -> 2026.2.1. This gets us 2026 field layouts
[among other
things](https://github.com/wpilibsuite/allwpilib/releases/tag/v2026.2.1)

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the "how") -->

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## Meta

Merge checklist:
- [ ] Pull Request title is [short, imperative
summary](https://cbea.ms/git-commit/) of proposed changes
- [ ] 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 v2025.3.2
- [ ] 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

photonlib-java-examples/aimandrange/build.gradle

@@ -1,6 +1,6 @@
 plugins {
     id "java"
-    id "edu.wpi.first.GradleRIO" version "2026.1.1"
+    id "edu.wpi.first.GradleRIO" version "2026.2.1"
 }
 
 sourceCompatibility = JavaVersion.VERSION_17
@@ -13,8 +13,8 @@ repositories {
 }
 
 wpi.maven.useDevelopment = true
-wpi.versions.wpilibVersion = "2026.1.1"
-wpi.versions.wpimathVersion = "2026.1.1"
+wpi.versions.wpilibVersion = "2026.2.1"
+wpi.versions.wpimathVersion = "2026.2.1"
 
 
 // Define my targets (RoboRIO) and artifacts (deployable files)