Auto merge of #19882 - aneeshusa:move-global-env-vars-to-servo, r=jdm

Move global CI environment variables to servo

Migrate RUST_BACKTRACE out of saltfs.
SCCACHE_IDLE_TIMEOUT has already been migrated.

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- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes help with servo/saltfs#770 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because they change the CI configuration

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1 files changed, 1 insertions, 0 deletions

diff --git a/etc/ci/buildbot_steps.yml b/etc/ci/buildbot_steps.yml
index f942cd00fe0..37380ca5349 100644
--- a/etc/ci/buildbot_steps.yml
+++ b/etc/ci/buildbot_steps.yml
@@ -1,4 +1,5 @@
 env:
+  RUST_BACKTRACE: '1'
   RUSTFLAGS: -Dwarnings
   CARGO_INCREMENTAL: "0"
   SCCACHE_IDLE_TIMEOUT: "600"