Fix small typos (#4041)

diff --git a/lib/src/executable.dart b/lib/src/executable.dart
index 9b03a24..c17ea57 100644
--- a/lib/src/executable.dart
+++ b/lib/src/executable.dart
@@ -208,7 +208,7 @@
 
 /// The result of a `getExecutableForCommand` command resolution.
 final class DartExecutableWithPackageConfig {
-  /// Can be a .dart file or a incremental snapshot.
+  /// Can be a .dart file or an incremental snapshot.
   final String executable;
 
   /// The package_config.json to run [executable] with. Or <null> if the VM
diff --git a/lib/src/validator/leak_detection.dart b/lib/src/validator/leak_detection.dart
index 2e3fd68..d5c2803 100644
--- a/lib/src/validator/leak_detection.dart
+++ b/lib/src/validator/leak_detection.dart
@@ -240,7 +240,7 @@
     // Unique identifiers are documented here:
     // https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_identifiers.html#identifiers-unique-ids
     //
-    // Maximum length of a access key is specified as 128 here:
+    // Maximum length of an access key is specified as 128 here:
     // https://docs.aws.amazon.com/IAM/latest/APIReference/API_AccessKey.html#API_AccessKey_Contents
     pattern:
         r'[^A-Z0-9]((?:A3T[A-Z0-9]|AKIA|AGPA|AIDA|AROA|AIPA|ANPA|ANVA|ASIA)[A-Z0-9]{12,128})[^A-Z0-9]',
diff --git a/test/token/token_authentication_test.dart b/test/token/token_authentication_test.dart
index 803e893..dd176b6 100644
--- a/test/token/token_authentication_test.dart
+++ b/test/token/token_authentication_test.dart
@@ -31,7 +31,7 @@
     await pub.shouldExit(1);
   });
 
-  test('with a invalid environment token fails with error', () async {
+  test('with an invalid environment token fails with error', () async {
     await servePackages();
     await d.validPackage().create();
     await d.tokensFile({