xege: fix url

[ericLemanissier]

the tag does not exist any more

caught by https://ericlemanissier.github.io/conan-center-lint-conandata/

Specify library name and version: xege/20.08

---

• I've read the contributing guidelines.
• I've used a recent Conan client version close to the currently deployed.
• I've tried at least one configuration locally with the conan-center hook activated.

[ericLemanissier]

The build is now finished. You can take a look at the results here

[conan-center-bot]

Conan v1 pipeline ✔️

All green in build 1 (53fd70a15b58687f43522f4aa997c1c49a38a147):

• xege/20.08:
  All packages built successfully! (All logs)

---

Conan v2 pipeline ✔️

Note: Conan v2 builds are now mandatory. Please read our discussion about it.

All green in build 1 (53fd70a15b58687f43522f4aa997c1c49a38a147):

• xege/20.08:
  All packages built successfully! (All logs)

[AbrilRBS]

Thanks a lot!
At some point we'll release the Conan Center backup sources generally so things like these would become less of an issue :)