ci: remove unused .github files

Signed-off-by: Christina Sørensen <christina@cafkafk.com>

.github/FUNDING.yml

@@ -1 +0,0 @@
-github: ogham

.github/workflows/unit-tests.yml

@@ -1,54 +0,0 @@
-name: Unit tests
-
-on:
-  push:
-    branches: [ master ]
-    paths:
-      - '.github/workflows/*'
-      - 'src/**'
-      - 'Cargo.*'
-      - build.rs
-  pull_request:
-    branches: [ master ]
-    paths:
-      - '.github/workflows/*'
-      - 'src/**'
-      - 'Cargo.*'
-      - build.rs
-
-env:
-  CARGO_TERM_COLOR: always
-
-jobs:
-  unit-tests:
-    runs-on: ${{ matrix.os }}
-
-    continue-on-error: ${{ matrix.rust == 'nightly' }}
-
-    strategy:
-      matrix:
-        os: [ubuntu-latest, macos-latest]
-        rust: [1.63.0, stable, beta, nightly]
-
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@v2
-
-      - name: Install Rust toolchain
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: ${{ matrix.rust }}
-          override: true
-
-      - name: Install cargo-hack
-        uses: actions-rs/cargo@v1
-        with:
-          command: install
-          args: cargo-hack
-
-      - name: Run unit tests
-        uses: actions-rs/cargo@v1
-        with:
-          command: hack
-          args: test --feature-powerset