chore(ci): Fail postgres tests if compiling them generates warnings

Signed-off-by: Joshua Potts <[email protected]>

Author: iamjpotts

.github/workflows/sqlx.yml

@@ -243,7 +243,7 @@ jobs:
         env:
           DATABASE_URL: postgres://postgres:password@localhost:5432/sqlx
           SQLX_OFFLINE_DIR: .sqlx
-          RUSTFLAGS: --cfg postgres="${{ matrix.postgres }}"
+          RUSTFLAGS: -D warnings --cfg postgres="${{ matrix.postgres }}"
 
       # Run the `test-attr` test again to cover cleanup.
       - run: >
@@ -254,7 +254,7 @@ jobs:
         env:
           DATABASE_URL: postgres://postgres:password@localhost:5432/sqlx
           SQLX_OFFLINE_DIR: .sqlx
-          RUSTFLAGS: --cfg postgres="${{ matrix.postgres }}"
+          RUSTFLAGS: -D warnings --cfg postgres="${{ matrix.postgres }}"
 
       - if: matrix.tls != 'none'
         run: >
@@ -264,7 +264,7 @@ jobs:
         env:
           DATABASE_URL: postgres://postgres:password@localhost:5432/sqlx?sslmode=verify-ca&sslrootcert=.%2Ftests%2Fcerts%2Fca.crt
           SQLX_OFFLINE_DIR: .sqlx
-          RUSTFLAGS: --cfg postgres="${{ matrix.postgres }}"
+          RUSTFLAGS: -D warnings --cfg postgres="${{ matrix.postgres }}"
 
       # Remove test artifacts
       - run: cargo clean -p sqlx
@@ -290,7 +290,7 @@ jobs:
           DATABASE_URL: postgres://postgres:password@localhost:5432/sqlx
           SQLX_OFFLINE: true
           SQLX_OFFLINE_DIR: .sqlx
-          RUSTFLAGS: --cfg postgres="${{ matrix.postgres }}"
+          RUSTFLAGS: -D warnings --cfg postgres="${{ matrix.postgres }}"
 
   postgres-ssl-auth:
     name: Postgres SSL Auth
@@ -322,7 +322,7 @@ jobs:
           --features any,postgres,macros,_unstable-all-types,runtime-${{ matrix.runtime }},tls-${{ matrix.tls }}
         env:
           DATABASE_URL: postgres://postgres@localhost:5432/sqlx?sslmode=verify-ca&sslrootcert=.%2Ftests%2Fcerts%2Fca.crt&sslkey=.%2Ftests%2Fcerts%2Fkeys%2Fclient.key&sslcert=.%2Ftests%2Fcerts%2Fclient.crt
-          RUSTFLAGS: --cfg postgres="${{ matrix.postgres }}"
+          RUSTFLAGS: -D warnings --cfg postgres="${{ matrix.postgres }}"
 
   mysql:
     name: MySQL