Bump lsp4j.version from 0.20.1 to 0.23.1

Bumps `lsp4j.version` from 0.20.1 to 0.23.1.

Updates `org.eclipse.lsp4j:org.eclipse.lsp4j` from 0.20.1 to 0.23.1
- [Release notes](https://github.com/eclipse-lsp4j/lsp4j/releases)
- [Changelog](https://github.com/eclipse-lsp4j/lsp4j/blob/main/CHANGELOG.md)
- [Commits](eclipse-lsp4j/lsp4j@v0.20.1...v0.23.1)

Updates `org.eclipse.lsp4j:org.eclipse.lsp4j.jsonrpc` from 0.20.1 to 0.23.1
- [Release notes](https://github.com/eclipse-lsp4j/lsp4j/releases)
- [Changelog](https://github.com/eclipse-lsp4j/lsp4j/blob/main/CHANGELOG.md)
- [Commits](eclipse-lsp4j/lsp4j@v0.20.1...v0.23.1)

---
updated-dependencies:
- dependency-name: org.eclipse.lsp4j:org.eclipse.lsp4j
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.eclipse.lsp4j:org.eclipse.lsp4j.jsonrpc
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

pom.xml

@@ -8,7 +8,7 @@
  <description>LemMinX is a XML Language Server Protocol (LSP), and can be used with any editor that supports LSP, to offer an outstanding XML editing experience</description>
  <properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
- <lsp4j.version>0.20.1</lsp4j.version>
+ <lsp4j.version>0.23.1</lsp4j.version>
  <junit.version>5.10.1</junit.version>
  </properties>
  <url>https://github.com/eclipse/lemminx</url>