Use dotnet 3.0, update sonarscanner tool

Author: joshuaduffy

Dockerfile

@@ -1,4 +1,4 @@
-FROM mcr.microsoft.com/dotnet/core/sdk:2.2-stretch
+FROM mcr.microsoft.com/dotnet/core/sdk
 
 LABEL "com.github.actions.name"="dotnet-sonarscanner"
 LABEL "com.github.actions.description"="sonarscanner for dotnet core"
@@ -10,14 +10,20 @@ LABEL "homepage"="https://github.com/Secbyte/dotnet-sonarscanner"
 LABEL "maintainer"="Joshua Duffy <mail@joshuaduffy.org>"
 
 RUN echo "deb http://http.us.debian.org/debian/ testing contrib main" >> /etc/apt/sources.list && \
+    wget -qO- https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor > microsoft.asc.gpg && \
+    mv microsoft.asc.gpg /etc/apt/trusted.gpg.d/ && \
+    wget -q https://packages.microsoft.com/config/debian/10/prod.list && \
+    mv prod.list /etc/apt/sources.list.d/microsoft-prod.list && \
+    chown root:root /etc/apt/trusted.gpg.d/microsoft.asc.gpg && \
+    chown root:root /etc/apt/sources.list.d/microsoft-prod.list && \
     apt-get update && \
-    apt-get install -y --no-install-recommends default-jre && \
+    apt-get install -y --no-install-recommends default-jre apt-transport-https aspnetcore-runtime-2.1 && \
     apt-get -t testing install -y --no-install-recommends python3.7 python3-distutils && \
     curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py && \
     python3.7 get-pip.py && \
     rm -rf /var/lib/apt/lists/* /var/cache/apt/archives/* && \
     apt-get autoremove -y && \
-    dotnet tool install dotnet-sonarscanner --tool-path . --version 4.6.2
+    dotnet tool install dotnet-sonarscanner --tool-path . --version 4.7.1
 
 ADD entrypoint.sh /entrypoint.sh
 

README.md

@@ -8,7 +8,7 @@ _Currently does not support username/password authentication and presumes you ar
 
 ```yaml
 - name: Sonarscanner for dotnet
-  uses: Secbyte/dotnet-sonarscanner@v1.1
+  uses: Secbyte/dotnet-sonarscanner@v1.2
   with:
     buildCommand: dotnet build .
     testCommand: dotnet test .