Merge #685: clang-tidy: Fix readability-redundant-string-init in headers

c39619e clang-tidy: Fix `readability-redundant-string-init` in headers (Hennadii Stepanov)

Pull request description:

  Split from bitcoin/bitcoin#26705 as was requested in bitcoin/bitcoin#26705 (comment).

  To test this PR, consider applying a diff as follows:
  ```diff
  --- a/src/.clang-tidy
  +++ b/src/.clang-tidy
  @@ -12,17 +12,9 @@ readability-redundant-declaration,
   readability-redundant-string-init,
   '
   WarningsAsErrors: '
  -bugprone-argument-comment,
  -bugprone-use-after-move,
  -misc-unused-using-decls,
  -modernize-use-default-member-init,
  -modernize-use-nullptr,
  -performance-for-range-copy,
  -performance-move-const-arg,
  -performance-unnecessary-copy-initialization,
  -readability-redundant-declaration,
   readability-redundant-string-init,
   '
   CheckOptions:
    - key: performance-move-const-arg.CheckTriviallyCopyableMove
      value: false
  +HeaderFilterRegex: '.'
  ```

ACKs for top commit:
  MarcoFalke:
    review ACK c39619e

Tree-SHA512: d7b61be17737f68b8bb40b084cf03f89eae86f4951da2aa000fde0c5245491a01dbb83e5d6e870c6bab4de2dbb5c0eb0dd6613da71592b3a27cf2000a45eaeeb

Author: MarcoFalke

src/qt/transactionrecord.h

@@ -76,12 +76,12 @@ class TransactionRecord
     static const int RecommendedNumConfirmations = 6;
 
     TransactionRecord():
-            hash(), time(0), type(Other), address(""), debit(0), credit(0), idx(0)
+            hash(), time(0), type(Other), debit(0), credit(0), idx(0)
     {
     }
 
     TransactionRecord(uint256 _hash, qint64 _time):
-            hash(_hash), time(_time), type(Other), address(""), debit(0),
+            hash(_hash), time(_time), type(Other), debit(0),
             credit(0), idx(0)
     {
     }