[CI] Remove 'TSan Runs' job

This frequently crashes and I don't think it's due to a real TSan race.

E.g. https://buildkite.com/swiftlint/swiftlint/builds/4912#0185c098-a803-4525-8df1-827d1c97ed01

```
swiftlint(373,0x1ecdd3a80) malloc: nano zone abandoned due to inability to preallocate reserved vm space.
Linting Swift files in current working directory
1 of 538 [                              ] ETA: 0s (13129 files/s)
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
ThreadSanitizer:DEADLYSIGNAL
==373==ERROR: ThreadSanitizer: SEGV on unknown address 0x000000000008 (pc 0x000102cbe380 bp 0x00016f50ee00 sp 0x00016f50edc0 T30753687)
==373==The signal is caused by a UNKNOWN memory access.
==373==Hint: address points to the zero page.
    #0 __tsan::ThreadClock::release(__tsan::DenseSlabAllocCache*, __tsan::SyncClock*) <null>:46801128 (libclang_rt.tsan_osx_dynamic.dylib:arm64e+0x2a380)
    #1 __tsan::Release(__tsan::ThreadState*, unsigned long, unsigned long) <null>:46801128 (libclang_rt.tsan_osx_dynamic.dylib:arm64e+0x7456c)
    #2 swift::runJobInEstablishedExecutorContext(swift::Job*) <null>:46801128 (libswift_Concurrency.dylib:arm64e+0x40588)
    #3 swift_job_runImpl(swift::Job*, swift::ExecutorRef) <null>:46801128 (libswift_Concurrency.dylib:arm64e+0x41404)
    #4 _dispatch_root_queue_drain <null>:46801128 (libdispatch.dylib:arm64e+0x15f90)
    #5 _dispatch_worker_thread2 <null>:46801128 (libdispatch.dylib:arm64e+0x167bc)
    #6 _pthread_wqthread <null>:46801128 (libsystem_pthread.dylib:arm64e+0x30c0)
    #7 start_wqthread <null>:46801128 (libsystem_pthread.dylib:arm64e+0x1e1c)

==373==Register values:
 x[0] = 0x0000000102a53458   x[1] = 0x0000000000000538   x[2] = 0x0000000000000000   x[3] = 0x0000000000000000
 x[4] = 0x0000000000000001   x[5] = 0x0000000000000000   x[6] = 0x0095000004220122   x[7] = 0x0000000000000001
 x[8] = 0x0000000000000008   x[9] = 0x0000000000000000  x[10] = 0x0000000000000000  x[11] = 0x0000000000000000
x[12] = 0x0000000000000020  x[13] = 0x0000000110904040  x[14] = 0x0000000000000000  x[15] = 0x0000000106251910
x[16] = 0x0000000104190960  x[17] = 0x0000000000200018  x[18] = 0x0000000000000000  x[19] = 0x000000010f5d3488
x[20] = 0x0000000109ca03f0  x[21] = 0x0000000102a53458  x[22] = 0x0000000109ca03f0  x[23] = 0x0000000109cc0078
x[24] = 0x00040c0000fd77c4  x[25] = 0x0000010000000000  x[26] = 0x00000002287898f8  x[27] = 0x0000000000000000
x[28] = 0x000000016f50f0e0     fp = 0x000000016f50ee00     lr = 0x0000000102cbe360     sp = 0x000000016f50edc0
ThreadSanitizer can not provide additional info.
SUMMARY: ThreadSanitizer: SEGV (libclang_rt.tsan_osx_dynamic.dylib:arm64e+0x2a380) in __tsan::ThreadClock::release(__tsan::DenseSlabAllocCache*, __tsan::SyncClock*)+0x174
==373==ABORTING
```

.buildkite/pipeline.yml

@@ -23,11 +23,3 @@ steps:
     commands:
       - echo "+++ Test"
       - bazel test --test_output=streamed --build_tests_only --features=tsan --test_timeout=1000 //Tests/...
-  - label: "TSan Runs"
-    commands:
-      - echo "--- Build"
-      - bazel build --noremote_accept_cached --config=release --features=tsan swiftlint
-      - echo "+++ Pre-cache SwiftLint Run"
-      - ./bazel-bin/swiftlint --progress --lenient
-      - echo "+++ Post-cache SwiftLint Run"
-      - ./bazel-bin/swiftlint --progress --lenient