PMM-13023 Add leading slash to home dashboard path #11653

Job	Run time
Tests (mysql:5.6, mongo:4.2, postgres:10, perconalab/pmm-server:3-dev-latest)	6m 9s
Tests (mysql:5.7, mongo:4.4, postgres:11, perconalab/pmm-server:3-dev-latest)	5m 53s
Tests (mysql:8.0, mongo:4.4, postgres:12, perconalab/pmm-server:3-dev-latest)	5m 54s
Tests (mysql:8.0, mongo:4.4, postgres:13, perconalab/pmm-server:3-dev-latest)	5m 58s
Tests (percona:5.6, percona/percona-server-mongodb:4.2, perconalab/percona-distribution-postgresq...	6m 5s
Tests (percona:5.7, percona/percona-server-mongodb:4.4, perconalab/percona-distribution-postgresq...	5m 46s
Tests (percona:8.0, percona/percona-server-mongodb:4.4, perconalab/percona-distribution-postgresq...	5m 53s
Tests (mariadb:10.2, mongo:4.4, postgres:9.4, perconalab/pmm-server:3-dev-latest)	5m 58s
Tests (mariadb:10.3, percona/percona-server-mongodb:4.4, postgres:9.5, perconalab/pmm-server:3-de...	5m 47s
Tests (mariadb:10.4, postgres:9.6, perconalab/pmm-server:3-dev-latest)	6m 19s
	59m 42s

Provide feedback