Bump pub to 37d05928939b3100e7e55c3dff922651db1de1e1

Changes:
```
> git log --format="%C(auto) %h %s" a817863..37d0592
 37d05928 Don't ignore 'packages/' over the root-dir (#3162)
 85e11718 Add in-memory cache to store version listings (#3163)
 46f79d5b Use source.hasMultipleVersions to decide when to show version constraint. (#3159)
 0e553a07 Warn against likely bad env-var name (#3146)
 30580bee Migrate src/git to null-safety (#3158)

```

Change-Id: Ic04937ad0adbeb228770087dedb25ccfcc4f3206
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/215202
Reviewed-by: Sarah Zakarias <[email protected]>
Commit-Queue: Sigurd Meldgaard <[email protected]>

Author: sigurdm

DEPS

@@ -139,7 +139,7 @@ vars = {
   "pool_rev": "7abe634002a1ba8a0928eded086062f1307ccfae",
   "process_rev": "56ece43b53b64c63ae51ec184b76bd5360c28d0b",
   "protobuf_rev": "c1eb6cb51af39ccbaa1a8e19349546586a5c8e31",
-  "pub_rev": "a817863ee93241ff36fce6856c6d12fd8fde0907",
+  "pub_rev": "37d05928939b3100e7e55c3dff922651db1de1e1",
   "pub_semver_rev": "a43ad72fb6b7869607581b5fedcb186d1e74276a",
   "resource_rev": "6b79867d0becf5395e5819a75720963b8298e9a7",
   "root_certificates_rev": "692f6d6488af68e0121317a9c2c9eb393eb0ee50",