migrations: rename symbols.signature to symbols.synopsis

For golang/go#37102

Change-Id: Ib7e24deca26fa06427e42bb6b175369af54b908e
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/291730
Trust: Julie Qiu <julie@golang.org>
Run-TryBot: Julie Qiu <julie@golang.org>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>

migrations/000065_rename_symbols_signature_to_synopsis.down.sql

@@ -0,0 +1,9 @@
+-- Copyright 2021 The Go Authors. All rights reserved.
+-- Use of this source code is governed by a BSD-style
+-- license that can be found in the LICENSE file.
+
+BEGIN;
+
+ALTER TABLE symbol_history RENAME synopsis TO signature;
+
+END;

migrations/000065_rename_symbols_signature_to_synopsis.up.sql

@@ -0,0 +1,12 @@
+-- Copyright 2021 The Go Authors. All rights reserved.
+-- Use of this source code is governed by a BSD-style
+-- license that can be found in the LICENSE file.
+
+BEGIN;
+
+ALTER TABLE symbol_history RENAME signature TO synopsis;
+
+COMMENT ON COLUMN symbol_history.synopsis IS
+'COLUMN synopsis is a one-line summary for the symbol.';
+
+END;