[BUG][RUST-SERVER] Is it possible to retire use of forked serde-xml-rs

Bug Report Checklist

• [x ] Have you provided a full/minimal spec to reproduce the issue?
• [x ] Have you validated the input using an OpenAPI validator (example)?
• [x ] What's the version of OpenAPI Generator used?
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• [x ] What's the actual output vs expected output?
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Description

Is it possible to retire use of the forked version of serde-xml-rs?

Currently this is generated in Cargo.toml:

# Crates included if required by the API definition
# TODO: this should be updated to point at the official crate once
# https://github.com/RReverser/serde-xml-rs/pull/45 is accepted upstream
serde-xml-rs = {git = "git://github.com/Metaswitch/serde-xml-rs.git" , branch = "master"}

I've hit a bug present in this forked version of serde-xml-rs with the string serializer, which isn't present in the upstream version (tested with 0.4.0). My workaround is to replace this with:

serde-xml-rs = 0.4.0

openapi-generator version

openapi-generator-cli 5.0.0-SNAPSHOT
commit : 6b877ef
built : 2020-06-23T19:45:17Z
source : https://github.com/openapitools/openapi-generator
docs : https://openapi-generator.tech/

OpenAPI declaration file content or url

n/a

Steps to reproduce

n/a

Related issues/PRs

n/a

Suggest a fix

See above

Inspect the generated Cargo.toml dependency entry and the generator path that produces it. Replace the forked serde-xml-rs reference with the upstream 0.4.0 dependency, then verify that generated Rust server projects use the upstream crate and no longer reference the fork.