[keyserver] Modify filename column in MariaDB uploads table to utf8

Summary:
Instead of just updating the filename column, I updated the default to `utf8_mb4` (the "real" utf8 encoding in MariaDB). That way if we create a future column, it will default to utf8.

I think added explicit annotations to keep the other columns the same, to avoid any weird effects.

Test Plan:
1. I tested that the migration works in my local environment
2. I tested that the `setup-db.js` query works by copy-pasting it into a MariaDB console in my local environment (with a different name for the table)
3. I then ran `SHOW FULL COLUMNS FROM` on both the migration result and the `setup-db.js` result to confirm they were the same: https://gist.github.com/Ashoat/0494344fa432995cf0219aed25fcb321
4. Finally, I confirmed that my repro (drag-n-drop a screenshot on macOS before it saves to desktop) no longer repro'd

Reviewers: atul, bartek

Reviewed By: atul, bartek

Subscribers: tomek, wyilio

Differential Revision: https://phab.comm.dev/D9403

keyserver/src/database/migration-config.js

@@ -539,6 +539,24 @@ const migrations: $ReadOnlyMap<number, () => Promise<mixed>> = new Map([
       );
     },
   ],
+  [
+    45,
+    () =>
+      dbQuery(
+        SQL`
+          ALTER TABLE uploads
+            CHARSET utf8mb4 COLLATE utf8mb4_bin,
+            MODIFY COLUMN type varchar(255)
+              CHARSET latin1 COLLATE latin1_swedish_ci NOT NULL,
+            MODIFY COLUMN filename varchar(255)
+              CHARSET utf8mb4 COLLATE utf8mb4_bin NOT NULL,
+            MODIFY COLUMN mime varchar(255)
+              CHARSET latin1 COLLATE latin1_swedish_ci NOT NULL,
+            MODIFY COLUMN secret varchar(255)
+              CHARSET latin1 COLLATE latin1_swedish_ci NOT NULL;
+        `,
+      ),
+  ],
 ]);
 const newDatabaseVersion: number = Math.max(...migrations.keys());
 

keyserver/src/database/setup-db.js

@@ -183,14 +183,14 @@ async function createTables() {
         thread bigint(20) DEFAULT NULL,
         uploader varchar(255) CHARSET latin1 COLLATE latin1_bin NOT NULL,
         container bigint(20) DEFAULT NULL,
-        type varchar(255) NOT NULL,
+        type varchar(255) CHARSET latin1 COLLATE latin1_swedish_ci NOT NULL,
         filename varchar(255) NOT NULL,
-        mime varchar(255) NOT NULL,
+        mime varchar(255) CHARSET latin1 COLLATE latin1_swedish_ci NOT NULL,
         content longblob NOT NULL,
-        secret varchar(255) NOT NULL,
+        secret varchar(255) CHARSET latin1 COLLATE latin1_swedish_ci NOT NULL,
         creation_time bigint(20) NOT NULL,
         extra json DEFAULT NULL
-      ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
+      ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;
 
       CREATE TABLE users (
         id varchar(255) CHARSET latin1 COLLATE latin1_bin NOT NULL,