Upgrade Bootsnap to v1.4.5

This may solve issues in development with
`Bootsnap::LoadPathCache::Store::NestedTransactionError`:

https://github.com/Shopify/bootsnap/pull/270

Gemfile.lock

@@ -108,7 +108,7 @@ GEM
     binding_ninja (0.2.3)
     binding_of_caller (0.8.0)
       debug_inspector (>= 0.0.1)
-    bootsnap (1.4.4)
+    bootsnap (1.4.5)
       msgpack (~> 1.0)
     bootstrap_form (4.2.0)
       actionpack (>= 5.0)
@@ -586,7 +586,7 @@ GEM
     mini_mime (1.0.1)
     mini_portile2 (2.4.0)
     minitest (5.11.3)
-    msgpack (1.3.0)
+    msgpack (1.3.1)
     multi_json (1.13.1)
     multi_xml (0.6.0)
     multipart-post (2.0.0)