Add gfortran as a dependency

Author: tmolteno

.github/workflows/build-necpp-wheels.yml

@@ -35,12 +35,12 @@ jobs:
         if: runner.os == 'Linux'
         run: |
           sudo apt-get update
-          sudo apt-get install -y swig autoconf automake libtool
+          sudo apt-get install -y swig autoconf automake libtool gfortran
 
       - name: Install build dependencies (macOS)
         if: runner.os == 'macOS'
         run: |
-          brew install swig autoconf automake libtool
+          brew install swig autoconf automake libtool gfortran
 
       - name: Configure necpp_src
         shell: bash
@@ -84,7 +84,7 @@ jobs:
       - name: Install build dependencies
         run: |
           sudo apt-get update
-          sudo apt-get install -y swig autoconf automake libtool
+          sudo apt-get install -y swig autoconf automake libtool gfortran
 
       - name: Configure necpp_src
         run: |

.github/workflows/build-pynec-wheels.yml

@@ -35,12 +35,12 @@ jobs:
         if: runner.os == 'Linux'
         run: |
           sudo apt-get update
-          sudo apt-get install -y swig autoconf automake libtool
+          sudo apt-get install -y swig autoconf automake libtool gfortran
 
       - name: Install build dependencies (macOS)
         if: runner.os == 'macOS'
         run: |
-          brew install swig autoconf automake libtool
+          brew install swig autoconf automake libtool gfortran
 
       - name: Configure necpp_src
         shell: bash
@@ -84,7 +84,7 @@ jobs:
       - name: Install build dependencies
         run: |
           sudo apt-get update
-          sudo apt-get install -y swig autoconf automake libtool
+          sudo apt-get install -y swig autoconf automake libtool gfortran
 
       - name: Configure necpp_src
         run: |