Drop reconnect: true from DB configs

We get flooded with these errors in tests:

```
WARNING: MYSQL_OPT_RECONNECT is deprecated and will be removed in a future version.
```

`reconnect: true` allows for automatic reconnection to the server in
the event that the server disconnects the client. One way that happens
is if the connection sits unused long enough to exceed the session
timeout. ARHP doesn't manage reconnection on its own so we can remove this.

This did require manually adding a `connection.reconnect!` to a test
where we tell the server to kill the connection. In that test we're
testing that calling `reconnect!` doesn't cause us to switch to the
wrong database, not the specific behavior of `reconnect: true`.

test/database.yml

@@ -36,7 +36,6 @@ test_pool_1_db_a:
   username: <%= mysql.user %>
   password: "<%= mysql.password %>"
   host: <%= mysql.host %>
-  reconnect: true
 
 # Mimic configurations as read by active_record_shards/ar_flexmaster
 test_pool_1_db_a_replica:
@@ -46,7 +45,6 @@ test_pool_1_db_a_replica:
   username: <%= mysql.user %>
   password: "<%= mysql.password %>"
   host: <%= mysql.host %>
-  reconnect: true
   slave: true
 
 test_pool_1_db_b:
@@ -56,7 +54,6 @@ test_pool_1_db_b:
   username: <%= mysql.user %>
   password: "<%= mysql.password %>"
   host: <%= mysql.host %>
-  reconnect: true
 
 test_pool_1_db_not_there:
   adapter: <%= adapter %>
@@ -65,7 +62,6 @@ test_pool_1_db_not_there:
   username: <%= mysql.user %>
   password: "<%= mysql.password %>"
   host: <%= mysql.host %>
-  reconnect: true
 
 test_pool_2_db_d:
   adapter: <%= adapter %>
@@ -75,7 +71,6 @@ test_pool_2_db_d:
   password: "<%= mysql.password %>"
   host: <%= mysql.host %>
   port: <%= mysql.port %>
-  reconnect: true
 
 test_pool_2_db_e:
   adapter: <%= adapter %>
@@ -85,7 +80,6 @@ test_pool_2_db_e:
   password: "<%= mysql.password %>"
   host: <%= mysql.host %>
   port: <%= mysql.port %>
-  reconnect: true
 
 test_pool_3_db_e:
   adapter: <%= adapter %>
@@ -95,7 +89,6 @@ test_pool_3_db_e:
   password:
   host: <%= mysql.host %>
   port: <%= mysql.port %>
-  reconnect: true
 
 # test_pool_1_db_c needs to be the last database defined in the file
 # otherwise the test_models_with_matching_hosts_and_non_matching_databases_issue_exists_without_arhp_patch
@@ -107,4 +100,3 @@ test_pool_1_db_c:
   username: <%= mysql.user %>
   password: "<%= mysql.password %>"
   host: <%= mysql.host %>
-  reconnect: true

test/test_arhp.rb

@@ -186,6 +186,8 @@ def test_underlying_assumption_about_test_db
       Pool2DbD.connection.execute("KILL #{thread_id}")
     end
 
+    switch_to_klass.connection.reconnect!
+
     # and finally, did mysql reconnect correctly?
     puts "\nAnd now we end up on #{current_database(switch_to_klass)}" if debug_me
     assert_equal expected_database, current_database(switch_to_klass)

test/three_tier_database.yml

@@ -43,7 +43,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
 
   # Mimic configurations as read by active_record_shards/ar_flexmaster
   test_pool_1_db_a_replica:
@@ -53,7 +52,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
     replica: true
 
   test_pool_1_db_b:
@@ -63,7 +61,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
 
   test_pool_1_db_c:
     adapter: <%= adapter %>
@@ -72,7 +69,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
 
   test_pool_1_db_not_there:
     adapter: <%= adapter %>
@@ -81,7 +77,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
 
   test_pool_1_db_shard_a:
     adapter: <%= adapter %>
@@ -90,7 +85,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
 
   test_pool_1_db_shard_b:
     adapter: <%= adapter %>
@@ -99,7 +93,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
 
   test_pool_1_db_shard_b_replica:
     adapter: <%= adapter %>
@@ -108,7 +101,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
     replica: true
 
   test_pool_1_db_shard_c:
@@ -118,7 +110,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
 
   test_pool_1_db_shard_c_replica:
     adapter: <%= adapter %>
@@ -127,7 +118,6 @@ test:
     username: <%= mysql.user %>
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
-    reconnect: true
     replica: true
 
   test_pool_2_db_shard_d:
@@ -138,7 +128,6 @@ test:
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
     port: <%= mysql.port %>
-    reconnect: true
 
   test_pool_2_db_shard_d_replica:
     adapter: <%= adapter %>
@@ -148,7 +137,6 @@ test:
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
     port: <%= mysql.port %>
-    reconnect: true
     replica: true
 
   test_pool_2_db_d:
@@ -159,7 +147,6 @@ test:
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
     port: <%= mysql.port %>
-    reconnect: true
 
   test_pool_2_db_e:
     adapter: <%= adapter %>
@@ -169,7 +156,6 @@ test:
     password: "<%= mysql.password %>"
     host: <%= mysql.host %>
     port: <%= mysql.port %>
-    reconnect: true
 
   test_pool_3_db_e:
     adapter: <%= adapter %>
@@ -179,4 +165,3 @@ test:
     password:
     host: <%= mysql.host %>
     port: <%= mysql.port %>
-    reconnect: true