Auto merge of #11959 - larsbergstrom:change_bucket_name, r=metajack

Change servo s3 build bucket name

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This will allow us to push to URLs like:
http://servo-builds.s3.amazonaws.com/nightly/mac
instead of:
http://servo-developer-preview.s3.amazonaws.com/nightly/mac

We can have different directories for channels, individual releases, etc.

r? @edunham @metajack

cc @tschneidereit

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- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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etc/ci/upload_nightly.sh

@@ -12,7 +12,7 @@ usage() {
 
 
 upload() {
-    s3cmd put "${2}" "s3://servo-developer-preview/nightly/${1}"
+    s3cmd put "${2}" "s3://servo-builds/nightly/${1}"
 }