migrations: remove experiments table

Fixes b/162749448

Change-Id: Ic183fb80a2a5a5a1ee45d149ed3a52770a01e9ee
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/262178
Trust: Jonathan Amsterdam <jba@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Julie Qiu <julie@golang.org>

migrations/000030_remove_experiments.down.sql

@@ -0,0 +1,23 @@
+-- Copyright 2020 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;
+
+CREATE TABLE experiments (
+    name text NOT NULL,
+    rollout integer DEFAULT 0 NOT NULL,
+    description text NOT NULL,
+    PRIMARY KEY (name),
+    CONSTRAINT experiments_rollout_check CHECK (((rollout >= 0) AND (rollout <= 100)))
+);
+COMMENT ON TABLE experiments IS
+'TABLE experiments contains data for running experiments.';
+COMMENT ON COLUMN experiments.name IS
+'COLUMN name is the name of the experiment.';
+COMMENT ON COLUMN experiments.rollout IS
+'COLUMN rollout is the percentage of total requests that are included for the experiment.';
+COMMENT ON COLUMN experiments.description IS
+'COLUMN description describes the experiment.';
+
+END;

migrations/000030_remove_experiments.up.sql

@@ -0,0 +1,9 @@
+-- Copyright 2020 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;
+
+DROP TABLE experiments;
+
+END;