fix: Update test expectations to include base ref detection warnings

The new base ref auto-detection feature logs warnings when it cannot
find a local branch that points to the merge-base. Updated integration
tests to expect these warning messages in their output.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: runningcode

tests/integration/_cases/build/build-upload-apk-all-uploaded.trycmd

@@ -2,6 +2,7 @@
 $ sentry-cli build upload tests/integration/_fixtures/build/apk.apk
 ? success
 [..]WARN[..]EXPERIMENTAL: The build subcommand is experimental. The command is subject to breaking changes and may be removed without notice in any release.
+  WARN    [..] No base branch reference found (no local branch points to merge-base)
 Successfully uploaded 1 file to Sentry
   - tests/integration/_fixtures/build/apk.apk (http[..]/wat-org/preprod/wat-project/42)
 

tests/integration/_cases/build/build-upload-apk-no-token.trycmd

@@ -2,6 +2,7 @@
 $ sentry-cli build upload tests/integration/_fixtures/build/apk.apk
 ? failed
 [..]WARN[..]EXPERIMENTAL: The build subcommand is experimental. The command is subject to breaking changes and may be removed without notice in any release.
+  WARN    [..] No base branch reference found (no local branch points to merge-base)
 error: Auth token is required for this request. Please run `sentry-cli login` and try again!
 
 Add --log-level=[info|debug] or export SENTRY_LOG_LEVEL=[info|debug] to see more output.

tests/integration/_cases/build/build-upload-apk.trycmd

@@ -2,6 +2,7 @@
 $ sentry-cli build upload tests/integration/_fixtures/build/apk.apk --head-sha test_head_sha
 ? success
 [..]WARN[..]EXPERIMENTAL: The build subcommand is experimental. The command is subject to breaking changes and may be removed without notice in any release.
+  WARN    [..] No base branch reference found (no local branch points to merge-base)
 Successfully uploaded 1 file to Sentry
   - tests/integration/_fixtures/build/apk.apk (http[..]/wat-org/preprod/wat-project/42)
 

tests/integration/_cases/build/build-upload-ipa.trycmd

@@ -2,6 +2,7 @@
 $ sentry-cli build upload tests/integration/_fixtures/build/ipa.ipa --head-sha test_head_sha
 ? success
 [..]WARN[..]EXPERIMENTAL: The build subcommand is experimental. The command is subject to breaking changes and may be removed without notice in any release.
+  WARN    [..] No base branch reference found (no local branch points to merge-base)
 Successfully uploaded 1 file to Sentry
   - tests/integration/_fixtures/build/ipa.ipa (http[..]/wat-org/preprod/wat-project/some-text-id)