fix(gctx): types are unsupported not unknown (#16109)

Address
#16103 (comment)

Author: epage

src/cargo/util/context/mod.rs

@@ -2155,10 +2155,7 @@ impl ConfigValue {
                     .collect::<CargoResult<_>>()?,
                 def,
             )),
-            v => bail!(
-                "found TOML configuration value of unknown type `{}`",
-                v.type_str()
-            ),
+            v => bail!("unsupported TOML configuration type `{}`", v.type_str()),
         }
     }
 

tests/testsuite/bad_config.rs

@@ -50,7 +50,7 @@ Caused by:
   failed to parse config at `http.proxy`
 
 Caused by:
-  found TOML configuration value of unknown type `float`
+  unsupported TOML configuration type `float`
 
 "#]])
         .run();
@@ -80,7 +80,7 @@ Caused by:
   failed to parse config at `http.proxy`
 
 Caused by:
-  found TOML configuration value of unknown type `datetime`
+  unsupported TOML configuration type `datetime`
 
 "#]])
         .run();

tests/testsuite/config_cli.rs

@@ -502,7 +502,7 @@ Caused by:
   failed to parse config at `a`
 
 Caused by:
-  found TOML configuration value of unknown type `datetime`
+  unsupported TOML configuration type `datetime`
 "#]],
     );
 }