use only ubuntu-latest for all tests

.github/workflows/build_examples.yml

@@ -2,13 +2,9 @@ name: build_examples
 on: [push]
 jobs:
   counter:
-    strategy:
-      matrix:
-        os: [ubuntu-latest, ubuntu-22.04, ubuntu-20.04]
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-
       - name: Add SSH Keys
         run: |
           mkdir ~/.ssh

.github/workflows/functional_simulation.yml

@@ -2,10 +2,7 @@ name: functional_simulation
 on: [push]
 jobs:
   uart:
-    strategy:
-      matrix:
-        os: [ubuntu-latest, ubuntu-22.04, ubuntu-20.04]
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
       - run: sudo apt install iverilog
@@ -13,10 +10,7 @@ jobs:
       - run: vvp sim.out
   
   fifo:
-    strategy:
-      matrix:
-        os: [ubuntu-latest, ubuntu-22.04, ubuntu-20.04]
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
       - run: sudo apt install iverilog

src/manta/fifo.sv

@@ -37,7 +37,7 @@ module fifo (
 	logic output_valid_pip_0;
 	logic output_valid_pip_1;
 
-	always @(posedge clk) begin
+	always_ff @(posedge clk) begin
 		if (input_ready && ~full)
 			write_pointer <= write_pointer + 1'd1;