Upgrade play-googleauth and play-secret-rotation to play-v30 ve…

…rsions

Keeping the version numbers low for now, i.e. `v2.4.0` for `com.gu.play-googleauth` and `v0.40` for `com.gu.play-secret-rotation` because if I upgrade to latest we're getting binary incompatibility error.

```
[error] (common / update) found version conflict(s) in library dependencies; some are suspected to be binary incompatible:
[error]
[error] 	* com.gu.play-secret-rotation:core_2.13:6.0.5 (early-semver) is selected over {6.0.4, 0.36}
[error] 	    +- com.gu.play-secret-rotation:play-v30_2.13:6.0.5    (depends on 6.0.5)
[error] 	    +- com.gu.play-secret-rotation:aws-parameterstore-secret-supplier-base_2.13:0.36 (depends on 0.36)
[error] 	    +- com.gu.play-googleauth:play-v30_2.13:3.0.5         (depends on 6.0.4)
```

Will address this in a future PR and after resolving another binary incompatibility error we're getting which is more complicated and actually blocks the Play 3 upgrade.

```
[error] 	* org.scala-lang.modules:scala-xml_2.13:2.2.0 (early-semver) is selected over {1.2.0, 1.3.0}
[error] 	    +- org.playframework:play-ws-standalone-xml_2.13:3.0.0 (depends on 2.2.0)
[error] 	    +- org.playframework.twirl:twirl-api_2.13:2.0.1       (depends on 2.2.0)
[error] 	    +- net.liftweb:lift-json_2.13:3.4.3                   (depends on 1.3.0)
[error] 	    +- com.typesafe.play:twirl-api_2.13:1.4.2             (depends on 1.2.0)
```

project/Dependencies.scala

@@ -51,8 +51,8 @@ object Dependencies {
   val macwire = "com.softwaremill.macwire" %% "macros" % "2.5.7" % "provided"
   val mockito = "org.mockito" % "mockito-all" % "1.10.19" % Test
   val paClient = "com.gu" %% "pa-client" % "7.0.5"
-  val playGoogleAuth = "com.gu.play-googleauth" %% "play-v28" % "2.2.7"
-  val playSecretRotation = "com.gu.play-secret-rotation" %% "play-v28" % "0.18"
+  val playGoogleAuth = "com.gu.play-googleauth" %% "play-v30" % "2.4.0"
+  val playSecretRotation = "com.gu.play-secret-rotation" %% "play-v30" % "0.40"
   val playSecretRotationAwsSdk = "com.gu.play-secret-rotation" %% "aws-parameterstore-sdk-v1" % "0.18"
   val quartzScheduler = "org.quartz-scheduler" % "quartz" % "2.3.2"
   val redisClient = "net.debasishg" %% "redisclient" % "3.42"