GP-1521: Increasing minimum supported Gradle version from 6.0 to 6.4

(Closes NationalSecurityAgency#3650)

Author: ryanmkurtz

DevGuide.md

@@ -34,7 +34,7 @@ You may not need all of these, depending on which portions you are building or d
       - https://adoptium.net/releases.html?variant=openjdk11&jvmVariant=hotspot
     - Amazon Corretto
       - https://docs.aws.amazon.com/corretto/latest/corretto-11-ug/downloads-list.html
-* Gradle 6 or 7
+* Gradle 6.4+ or 7.x
     - https://gradle.org/releases/
 * A C/C++ compiler - We use GCC on Linux, Xcode (Clang) on macOS, and Visual Studio (2017 or later) on Windows.
     - https://gcc.gnu.org/

Ghidra/application.properties

@@ -2,7 +2,7 @@ application.name=Ghidra
 application.version=10.1
 application.release.name=DEV
 application.layout.version=1
-application.gradle.min=6.0
+application.gradle.min=6.4
 application.java.min=11
 application.java.max=
 application.java.compiler=11

README.md

@@ -38,7 +38,7 @@ To create the latest development build for your platform from this source reposi
 
 ##### Install build tools:
 * [JDK 11 64-bit][jdk11]
-* [Gradle 6 or 7][gradle]
+* [Gradle 6.4+ or 7.x][gradle]
 * make, gcc, and g++ (Linux/macOS-only)
 * [Microsoft Visual Studio][vs] (Windows-only)