use equals filter by default (#3145)

Now that we've filters moved from concatenated strings into slices it's possible for selector scopes to prefer equals over contains as the standard matching behavior.  This will minimize the possibility of pulling in unintended resources for details and restore.

<!-- PR description-->

---

#### Does this PR need a docs update or release note?

- [x] ⛔ No

#### Type of change

- [x] 🧹 Tech Debt/Cleanup

#### Test Plan

- [x] 💪 Manual
- [x] ⚡ Unit test
- [x] 💚 E2E

src/pkg/selectors/scopes_test.go

@@ -572,13 +572,13 @@ func (suite *SelectorScopesSuite) TestScopesPII() {
 				`"pass":"Pass"`,
 				`"fail":"Fail"`,
 				`"foo":"EQ:bar"`,
-				`"qux":"Cont:fnords,smarf"`,
+				`"qux":"EQ:fnords,smarf"`,
 			},
 			containsPlain: []string{
 				`"pass":"Pass"`,
 				`"fail":"Fail"`,
 				`"foo":"EQ:bar"`,
-				`"qux":"Cont:fnords,smarf"`,
+				`"qux":"EQ:fnords,smarf"`,
 			},
 		},
 	}

src/pkg/selectors/selectors.go

@@ -585,11 +585,7 @@ func filterize(
 		return defaultFilter(targets)
 	}
 
-	if len(targets) == 1 {
-		return filters.Equal(targets)
-	}
-
-	return filters.Contains(targets)
+	return filters.Equal(targets)
 }
 
 // pathFilterFactory returns the appropriate path filter

src/pkg/selectors/selectors_test.go

@@ -439,8 +439,8 @@ func (suite *SelectorSuite) TestSelector_pii() {
 					ResourceOwners: filterFor(scopeConfig{}, "owner_1", "owner_2"),
 				}
 			},
-			expect:      `{"resourceOwners":"Cont:***,***","discreteOwner":"***"}`,
-			expectPlain: `{"resourceOwners":"Cont:owner_1,owner_2","discreteOwner":"owner"}`,
+			expect:      `{"resourceOwners":"EQ:***,***","discreteOwner":"***"}`,
+			expectPlain: `{"resourceOwners":"EQ:owner_1,owner_2","discreteOwner":"owner"}`,
 		},
 		{
 			name: "one scope each type",
@@ -456,14 +456,14 @@ func (suite *SelectorSuite) TestSelector_pii() {
 			},
 			//nolint:lll
 			expect: `{"service":1,` +
-				`"resourceOwners":"Cont:***,***",` +
+				`"resourceOwners":"EQ:***,***",` +
 				`"discreteOwner":"***",` +
 				`"exclusions":[{"ExchangeMail":"Pass","ExchangeMailFolder":"PathCont:***","category":"Identity:***","type":"Identity:***"}],` +
 				`"filters":[{"ExchangeMail":"Pass","ExchangeMailFolder":"PathSfx:***","category":"Identity:***","type":"Identity:***"}],` +
 				`"includes":[{"ExchangeMail":"Pass","ExchangeMailFolder":"PathPfx:***","category":"Identity:***","type":"Identity:***"}]}`,
 			//nolint:lll
 			expectPlain: `{"service":1,` +
-				`"resourceOwners":"Cont:owner_1,owner_2",` +
+				`"resourceOwners":"EQ:owner_1,owner_2",` +
 				`"discreteOwner":"owner",` +
 				`"exclusions":[{"ExchangeMail":"Pass","ExchangeMailFolder":"PathCont:e","category":"Identity:ExchangeMailFolder","type":"Identity:ExchangeMail"}],` +
 				`"filters":[{"ExchangeMail":"Pass","ExchangeMailFolder":"PathSfx:f","category":"Identity:ExchangeMailFolder","type":"Identity:ExchangeMail"}],` +