fix(pg_backend): correct set idle_in_transaction_session_timeout statement (#5304)

* fix(metasrv): correct `backend` field configuration

* refactor!: added `#[serde(rename_all = "snake_case")]` macro to the `BackendImpl` enum

* fix(metasrv): correct `set idle_in_transaction_session_timeout` statement

* build: enable `pg_backend` by default

.github/actions/build-linux-artifacts/action.yml

@@ -53,7 +53,7 @@ runs:
       uses: ./.github/actions/build-greptime-binary
       with:
         base-image: ubuntu
-        features: servers/dashboard
+        features: servers/dashboard,pg_kvbackend
         cargo-profile: ${{ inputs.cargo-profile }}
         artifacts-dir: greptime-linux-${{ inputs.arch }}-${{ inputs.version }}
         version: ${{ inputs.version }}
@@ -71,7 +71,7 @@ runs:
       if: ${{ inputs.arch == 'amd64' && inputs.dev-mode == 'false' }} # Builds greptime for centos if the host machine is amd64.
       with:
         base-image: centos
-        features: servers/dashboard
+        features: servers/dashboard,pg_kvbackend
         cargo-profile: ${{ inputs.cargo-profile }}
         artifacts-dir: greptime-linux-${{ inputs.arch }}-centos-${{ inputs.version }}
         version: ${{ inputs.version }}

.github/workflows/nightly-ci.yml

@@ -96,7 +96,7 @@ jobs:
         with:
           distribution: Ubuntu-22.04
       - name: Running tests
-        run: cargo nextest run -F dashboard
+        run: cargo nextest run -F dashboard -F pg_kvbackend
         env:
           CARGO_BUILD_RUSTFLAGS: "-C linker=lld-link"
           RUST_BACKTRACE: 1