sqlite crash during update

[aryairani]

this transcript reproduces: doc-update-crash2.md

```ucm
.> pull unison.public.base.latest base
```

```unison
Unit.doc = {{  }}
```

```ucm
.base> update
```

⚙️   Processing stanza 3 of 3.SqliteQueryException
    { sql = "SELECT object.id
            FROM object
            JOIN hash ON object.primary_hash_id = hash.id
            WHERE hash.base32 = ? COLLATE NOCASE"
    , params = ""06kjlva47q3gbkmuvcflvpkalc47afp7shs79dla19jk2rg5sggrm3su0e9kosb211881gchtu6ha1fb1n899dhde002f0cd21buidg""
    , exception = ExpectedExactlyOneRowException
        { rows = "[]" }
    , callStack = []
    , connection = Connection
        { name = "main"
        , file = "/private/var/folders/rr/tdb_8nr96xl2v4t8n2f2x40w0000gn/T/transcript-eb6e4a5363309735/.unison/v2/unison.sqlite3"
        }
    , threadId = ThreadId 15
    }

Possible connections to #3376 #3288 #3369?

[aryairani]

This transcript doesn't crash if you replace update with update.nopatch

[aryairani]

In M5i this no longer crashes