Fix test failures seen on buildbot where file_key_management plugin

is linked statically and dynamic plugin is not available.

mysql-test/suite/encryption/t/filekeys_plugin_exists.inc

+if (!$FILE_KEY_MANAGEMENT_SO)
+{
+  --skip Needs dynamic file_key_management plugin
+}

mysql-test/suite/encryption/t/innodb-bad-key-change2.test

@@ -4,6 +4,7 @@
 -- source include/not_valgrind.inc
 # Avoid CrashReporter popup on Mac
 -- source include/not_crashrep.inc
+-- source filekeys_plugin_exists.inc
 #
 # MDEV-8750: Server crashes in page_cur_is_after_last on altering table using a wrong encryption key
 #

mysql-test/suite/encryption/t/innodb-bad-key-change3.test

@@ -4,7 +4,7 @@
 -- source include/not_valgrind.inc
 # Avoid CrashReporter popup on Mac
 -- source include/not_crashrep.inc
-
+-- source filekeys_plugin_exists.inc
 #
 # MDEV-8772: Assertion failure in file ha_innodb.cc line 20027 when importing page compressed and encrypted tablespace using incorrect keys
 #

mysql-test/suite/encryption/t/innodb-bad-key-change4.test

@@ -4,6 +4,7 @@
 -- source include/not_valgrind.inc
 # Avoid CrashReporter popup on Mac
 -- source include/not_crashrep.inc
+-- source filekeys_plugin_exists.inc
 #
 # MDEV-8768: Server crash at file btr0btr.ic line 122 when checking encrypted table using incorrect keys
 #

mysql-test/suite/encryption/t/innodb-bad-key-change5.test

@@ -4,6 +4,7 @@
 -- source include/not_valgrind.inc
 # Avoid CrashReporter popup on Mac
 -- source include/not_crashrep.inc
+-- source filekeys_plugin_exists.inc
 #
 # MDEV-8769: Server crash at file btr0btr.ic line 122 when defragmenting encrypted table using incorrect keys
 #

mysql-test/suite/encryption/t/innodb_onlinealter_encryption.test

@@ -59,7 +59,7 @@ set autocommit=1;
 --let $wait_condition=SELECT COUNT(*) = 0 FROM INFORMATION_SCHEMA.INNODB_TABLESPACES_ENCRYPTION WHERE MIN_KEY_VERSION = 0
 --source include/wait_condition.inc
 
---sleep 5
+--sleep 10
 --let SEARCH_PATTERN=foobar
 --echo # t1 yes on expecting NOT FOUND
 -- let SEARCH_FILE=$t1_IBD
@@ -110,7 +110,7 @@ SHOW CREATE TABLE t5;
 SHOW CREATE TABLE t6;
 SHOW CREATE TABLE t7;
 
---sleep 5
+--sleep 10
 --let SEARCH_PATTERN=foobar
 --echo # t1 yes on expecting NOT FOUND
 -- let SEARCH_FILE=$t1_IBD