update README to reflect removal of -PscoverageCompileOnly

Author: maiflai

README.md

@@ -105,24 +105,17 @@ scoverage {
 }
 ``` 
 
-### Run without normal compilation
-
-By default, running any of the plugin tasks will compile the code both using "normal" compilation (`compileScala`)
-and using the scoverage scalac plugin (`compileScoverageScala`).
-
-In cases where you only wish to generate reports / validate coverage, but are not interested in publishing the code,
-it is possible to only compile the code with the scoverage scalac plugin, thus reducing build times significantly.
-In order to do so, simply add the arguments `-PscoverageCompileOnly` to the gradle execution.
-For example: `gradle reportScoverage -PscoverageCompileOnly`.
-
-Note that this mode is incompatible with parallel builds in multi-module projects.
-
 ### Compatibility with Consistent Versions Plugin
 
 In order for the plugin to work alongside [Palantir's consistent versions plugin](https://github.com/palantir/gradle-consistent-versions),
 the Scala version must be manually configured (via `scoverageScalaVersion`); otherwise, the plugin will attempt to
 resolve the compilation classpath, which is prohibited by the versions plugin.
 
+Migration to 8.x
+----------------
+
+* Running without normal compilation is no longer supported.
+
 Migration to 7.x
 ----------------