Removed the use of any and enabled the rule in eslint.

Now according to me the conversion is final.
Testing is required.

overlord/src/app/settings/settings.service.ts

@@ -6,35 +6,37 @@ import { catchError } from 'rxjs/operators';
 import { ErrorLoggerService } from '../core/error-logger.service';
 import { Product } from '../core/product';
 
+import { LockInfo } from './lock-info';
+
 const serviceName = 'SettingsService';
 
 @Injectable({ providedIn: 'root' })
 export class SettingsService {
   constructor(private http: HttpClient, private log: ErrorLoggerService) {}
 
-  getLockInformation(): Observable<any> {
+  getLockInformation(): Observable<LockInfo> {
     const url = '/api/lock-information';
-    return <Observable<any>>(
+    return <Observable<LockInfo>>(
       this.http
-        .get<any>(url)
+        .get<LockInfo>(url)
         .pipe(catchError(this.log.handleError(serviceName, 'getLockInformation')))
     );
   }
 
-  setLockInformation(lockInformation: any): Observable<any> {
+  setLockInformation(lockInformation: LockInfo): Observable<LockInfo> {
     const url = '/api/lock-information';
-    return <Observable<any>>(
+    return <Observable<LockInfo>>(
       this.http
-        .post<any>(url, lockInformation)
+        .post<LockInfo>(url, lockInformation)
         .pipe(catchError(this.log.handleError(serviceName, 'setLockInformation')))
     );
   }
 
-  deleteLockInformation(): Observable<any> {
+  deleteLockInformation(): Observable<LockInfo> {
     const url = '/api/lock-information';
-    return <Observable<any>>(
+    return <Observable<LockInfo>>(
       this.http
-        .delete<any>(url)
+        .delete<LockInfo>(url)
         .pipe(catchError(this.log.handleError(serviceName, 'deleteLockInformation')))
     );
   }
@@ -51,34 +53,36 @@ export class SettingsService {
       .pipe(catchError(this.log.handleError(serviceName, 'resetStock')));
   }
 
-  rebaseDatabase(date: string): Observable<boolean> {
+  rebaseDatabase(date: string): Observable<{}> {
     const url = '/api/rebase';
-    return <Observable<any>>(
+    return <Observable<{}>>(
       this.http
-        .post<any>(`${url}/${date}`, {})
+        .post<{}>(`${url}/${date}`, {})
         .pipe(catchError(this.log.handleError(serviceName, 'rebaseDatabase')))
     );
   }
 
-  setMaintenance(enable: boolean): Observable<any> {
+  setMaintenance(enable: boolean): Observable<{ enabled: boolean; user: string }> {
     const url = '/api/maintenance';
-    return this.http
-      .post<any>(url, { enabled: enable })
+    return <Observable<{ enabled: boolean; user: string }>>this.http
+      .post<{ enabled: boolean; user: string }>(url, { enabled: enable })
       .pipe(catchError(this.log.handleError(serviceName, 'setMaintenance')));
   }
 
-  getMaintenance(): Observable<any> {
+  getMaintenance(): Observable<{ enabled: boolean; user: string }> {
     const url = '/api/maintenance';
-    return <Observable<any>>(
-      this.http.get<any>(url).pipe(catchError(this.log.handleError(serviceName, 'getMaintenance')))
+    return <Observable<{ enabled: boolean; user: string }>>(
+      this.http
+        .get<{ enabled: boolean; user: string }>(url)
+        .pipe(catchError(this.log.handleError(serviceName, 'getMaintenance')))
     );
   }
 
-  checkDatabaseIntegrity(): Observable<any> {
+  checkDatabaseIntegrity(): Observable<{ 'Duplicate Attendances Fixed': number }> {
     const url = '/api/db-integrity';
-    return <Observable<any>>(
+    return <Observable<{ 'Duplicate Attendances Fixed': number }>>(
       this.http
-        .post<any>(url, {})
+        .post<{ 'Duplicate Attendances Fixed': number }>(url, {})
         .pipe(catchError(this.log.handleError(serviceName, 'checkDatabaseIntegrity')))
     );
   }